# Age and generation: report

Chapter 3.7 of The Public Mind, by Vishal Singh (NYU Stern). Generated from the chapter's data files; the reading version is at https://vishalsingh.org/politics/age-and-generation. Table n of this report is figure n of the chapter.

## Identification

- Title: Age and generation
- Chapter: 3.7 (Part III, Participation and coalitions; Coalitions and political differences)
- Question: How do age and birth cohort relate to party support, and what can repeated surveys separate?
- Dek: In the CES, two-party presidential voters under thirty were more Democratic than those sixty-five and older by +22.2 points in 2020 and +15.0 in 2024.
- Grain: individuals
- Status: draft
- Published: 2026-10-03
- Updated: not revised
- Data sources:
  - ANES Cumulative Data File. Cumulative Data File: presidential vote, party identification, age and birth cohort, presidential elections 1952-2024; years: 1948-2024 (33 study years; even years only after 2004; no 2006, 2010 or 2014 study); weights: post-election weight where available, otherwise VCF0009z; weight_ftf and weight_web for interview-mode estimates
  - Cooperative Election Study. Cumulative Common Content: presidential vote 2008-2024 and party identification 2006-2024; years: 2006-2024 (every year; self-reported turnout is available in the 10 even years); weights: weight_cumulative; weight_post (2012, 2016, 2020) and vvweight for sensitivity rows
  - State presidential returns. State presidential returns 1976-2024, used only for the certified national two-party share; years: 1976-2024 (13 elections); weights: none (full counts)
- Canonical URL: https://vishalsingh.org/politics/age-and-generation
- Report: https://vishalsingh.org/politics/age-and-generation/report
- Markdown: https://vishalsingh.org/politics/age-and-generation/report.md
- BibTeX key: singh2026ageandgeneration

```bibtex
@misc{singh2026ageandgeneration,
  author = {Singh, Vishal},
  title = {Age and generation},
  year = {2026},
  url = {https://vishalsingh.org/politics/age-and-generation},
  note = {In The Public Mind. Published 3 October 2026.}
}
```

## Principal estimates

The facts the dek and the opening prose cite, in order of appearance.

| Estimand | Population | Period | Value | Interval | n | Weights | Source | Fact id |
| --- | --- | --- | ---: | --- | ---: | --- | --- | --- |
| Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 | +22.2 | 95% CI 19.9 to 24.4 | 16,255 | weight_cumulative | Cooperative Election Study | ces_gap_2020 |
| Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2024 | +15.0 | 95% CI 11.8 to 18.3 | 18,087 | weight_cumulative | Cooperative Election Study | ces_gap_2024 |
| weighted Democratic share | two-party presidential voters aged 18 to 29 | 2008 | 67.2% | 95% CI 65.2% to 69.2% | 3,327 | weight_cumulative | Cooperative Election Study | ces_young_2008 |
| weighted Democratic share | two-party presidential voters aged 65 and over | 2008 | 42.7% | 95% CI 41.0% to 44.5% | 4,477 | weight_cumulative | Cooperative Election Study | ces_old_2008 |
| Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008 | +24.5 | 95% CI 21.8 to 27.1 | 7,804 | weight_cumulative | Cooperative Election Study | ces_gap_2008 |
| Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2024 | +23.0 | 95% CI 19.1 to 26.9 | 14,103 | vvweight (validated-voter weight, for respondents whose registration was matched to voter-file records) | Cooperative Election Study | ces_vv_gap_2024 |
| weighted Democratic share | two-party presidential voters (age may be missing) | 2024 | 54.5% | 95% CI 52.3% to 56.7% | 3,933 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File | anes_share_2024 |
| certified Democratic share of the two-party vote | ballots counted for the two major-party candidates | 2024 | 49.2% |   |   | none (full counts) | State presidential returns | cert_share_2024 |
| weighted Democratic share | two-party presidential voters | 2024 | 49.0% | 95% CI 48.2% to 49.7% | 42,008 | weight_cumulative | Cooperative Election Study | ces_share_2024 |
| count of respondents | two-party presidential voters with a known age | presidential elections 1952 to 2024 | 33,768 |   |   | none (count) | ANES Cumulative Data File | n_anes_voters |
| count of elections | ANES presidential election studies | presidential elections 1952 to 2024 | 19 |   |   | none (count) | ANES Cumulative Data File | n_anes_elections |
| count of respondents | two-party presidential voters with a known age | presidential elections 2008 to 2024 | 188,145 |   |   | none (count) | Cooperative Election Study | n_ces_voters |
| definition of the suppression floor | floor for a published survey cell | all years | 100 |   |   | none (definition) | ANES Cumulative Data File | floor_n |

## Findings

In the Cooperative Election Study (CES), 67.2% (95% CI 65.2% to 69.2%) of two-party voters under thirty and 42.7% (95% CI 41.0% to 44.5%) of two-party voters sixty-five and older voted for the Democratic presidential candidate in 2008, a gap of +24.5 (95% CI 21.8 to 27.1) points. The gap was +22.2 (95% CI 19.9 to 24.4) in 2020 and +15.0 (95% CI 11.8 to 18.3) in 2024. Among CES voters whose registration was matched to voter-file records the 2024 gap is +23.0 (95% CI 19.1 to 26.9), so the size of the recent fall depends on which voters are counted. The American National Election Studies (ANES) are the second survey, and their 2024 sample leans Democratic. Its two-party Democratic share, 54.5% (95% CI 52.3% to 56.7%), is above the certified count of 49.2%, while the CES share, 49.0% (95% CI 48.2% to 49.7%), is close to it, so the ANES age gaps are read beside the CES in the section on 2024.

A difference between age groups mixes three things. Age is what happens to a person as they get older. Period is what happens to every voter at one election, such as a landslide or a recession. Birth cohort is what people born in the same years share, such as the events of their teenage years, and a cohort is the group born in those years. The three are tied by arithmetic, because birth year equals election year minus age. A survey that records age and the election year already holds birth year, and no repeated survey can separate all three effects without an assumption [1] [2]. This chapter reports the age gap in the vote and in party identification from two surveys, follows birth cohorts from election to election, and then shows in the same data how far an estimated age effect moves with the assumption chosen.

The ANES Cumulative Data File supplies the vote of 33,768 respondents in 19 presidential elections from 1952 to 2024 who reported voting for the Democratic or the Republican candidate and gave an age of eighteen or older. The CES, an online panel, supplies 188,145 such respondents in the elections from 2008 to 2024. Such a respondent is a two-party voter, and a Democratic share is the share of two-party voters who reported a Democratic vote. Party identification counts Democrats and Republicans, with leaners included. The age groups are eighteen to twenty-nine, thirty to forty-four, forty-five to sixty-four and sixty-five and older, the bands that Chapter 3.2, The two coalitions (https://vishalsingh.org/politics/the-two-coalitions) uses for the age make-up of each party's voters. (Note: Every interval is a 95% confidence interval from the Kish effective sample size [3] on the survey weights, and it treats the weighted sample as a simple random sample. The CES is an opt-in panel, so its intervals leave out how respondents joined the panel. A cell needs at least 100 respondents and an effective sample of 100 to be shown, and smaller cells are left blank. ANES vote shares use the post-election weight in the elections where the file has one (1996, 2000, 2004, 2008, 2016, 2020 and 2024) and the full-sample weight otherwise, which includes 2012. CES shares use the cumulative-file weight, which is proportional within each election to the pre-election weight and is the one weight defined for every election. The vote is a post-election item, and the 2024 section checks the choice against the post-election weight. The methods note in the appendix names the weight of each estimate.)

### Three comparisons, and what each can say

A repeated survey offers three ways to compare voters, and each holds a different quantity fixed. Comparing age groups inside one election holds the period fixed, and it mixes age with birth cohort, because the older voters in an election were also born earlier. Comparing one age group across elections holds age fixed, and it mixes period with birth cohort, because the voters under thirty in two elections were born in different years. Following a birth cohort from one election to the next holds the cohort fixed, and it mixes age with period, because the cohort grows older and the election changes. Each comparison is the sum of two of the three effects, and none isolates one of them. The estimates of all three come near the end of the chapter (Table 8 and Table 9), after the descriptive evidence that uses them.

### The youngest voters were more Democratic than the oldest from 2008 to 2020

Table 1 plots the Democratic share of the two-party vote in each ANES election by age group. Before 2004 the sign of the gap between the youngest and oldest groups (Table 3) varies from one election to the next. The gap was +2.9 (95% CI −5.9 to 11.8) points in 1992. Its interval is above zero in 1964, in 1972 and in every election from 2004 to 2020, which is 7 of the 16 elections with enough voters under thirty to publish, and it includes zero in the rest. In 3 elections (1960, 1996 and 2000) the youngest group has too few respondents for a published cell. The gap was +22.6 (95% CI 12.2 to 33.0) in 2008 and +17.0 (95% CI 11.0 to 23.1) in 2020. In 2024 the youngest group, at 56.3% (95% CI 48.9% to 63.6%), is within about a point of the oldest, at 57.4% (95% CI 53.7% to 61.1%), and the interval for the gap, −1.1 (95% CI −9.4 to 7.1), includes zero.

Table 1. The ANES age gap in the Democratic vote was above zero in every election from 2004 to 2020 and included zero in 2024

Table 2 gives the same comparison in the CES, whose larger samples of young voters allow five age bands. In 2008, 2012, 2016 and 2020 the band aged thirty to forty-four is more Democratic than the band forty-five to sixty-four, which is more Democratic than the band sixty-five and older. Every interval for those two differences excludes zero. The two youngest bands are not always separated from their neighbors. In 2012 the band eighteen to twenty-four differs from the band twenty-five to twenty-nine by +0.5 (95% CI −4.3 to 5.2) points, and the band twenty-five to twenty-nine differs from the band thirty to forty-four by +2.9 (95% CI −0.9 to 6.7). The gap between the two end groups was between +18.7 and +24.5 points in those four elections, each with an interval above zero, and it was +15.0 (95% CI 11.8 to 18.3) in 2024. In 2024 the order of the two oldest bands is not settled: the band forty-five to sixty-four differs from the band sixty-five and older by −1.6 (95% CI −3.2 to 0.0) points. The two youngest bands differ by +0.5 to +5.0 points across the five elections, so the gap between the end groups is not mainly a difference between the very youngest voters and the rest.

Table 2. In every CES election from 2008 to 2020 the Democratic share was lower among voters forty-five to sixty-four than among voters thirty to forty-four, and lower again among voters sixty-five and older

Both figures compare age groups inside each election and follow one age group across elections, so both mix age with birth year. The voters under thirty in 2008 and in 2024 were born in different years, and so were the voters sixty-five and older.

### The 2024 CES fall is not detectable among voters matched to registration records

Between 2020 and 2024 the CES gap changed by −7.1 (95% CI −11.1 to −3.2) points among all voters. The ANES gap changed by −18.2 (95% CI −28.4 to −7.9) points, from +17.0 (95% CI 11.0 to 23.1) in 2020 to −1.1 (95% CI −9.4 to 7.1) in 2024, an interval that includes zero. The CES file also holds a weight, called the validated-voter weight, for voters whose registration could be matched to a voter-file record, which this chapter calls matched voters. Among them the gap was +22.8 (95% CI 20.1 to 25.4) in 2020 and +23.0 (95% CI 19.1 to 26.9) in 2024, a change of +0.2 (95% CI −4.5 to 4.9) points. With the standard weight on the same matched voters the 2024 gap is +22.2 (95% CI 17.9 to 26.5) and its change from 2020 is −0.6 (95% CI −5.6 to 4.5) points (Table 3). Both intervals extend below zero by several points, so the data show no detectable fall among matched voters and do not show that none occurred. The change among all voters minus the change among matched voters is −6.6 (95% CI −10.2 to −2.8) points with the standard weight and −7.3 (95% CI −11.8 to −3.0) with the validated-voter weight (bootstrap intervals), so the two changes differ by more than sampling error.

For the age gap, the difference between the estimates is associated with the sample and not with the weight. On the same matched voters the validated-voter weight moves the 2024 gap by +0.8 (95% CI −3.0 to 4.8) points, an interval that includes zero. The gap among matched voters is above the gap among all voters by +7.2 (95% CI 3.8 to 10.6) points (bootstrap intervals). Chapter 3.6, The gender gap in attitudes and votes (https://vishalsingh.org/politics/the-gender-gap) finds that the weight matters on the same respondents for the gender gap. The share of voters under thirty who could be matched fell from 66.9% in 2020 to 45.5% in 2024, and the share among voters sixty-five and older was 87.4% and 84.6%. In 2024 matched voters under thirty were 68.2% (95% CI 64.1% to 72.4%) Democratic and unmatched voters under thirty 54.5% (95% CI 50.2% to 58.8%), a difference of +13.8 (95% CI 7.8 to 19.7) points. In 2020 the difference was +3.0 (95% CI −1.1 to 7.1) points, an interval that includes zero. The data cannot say why the unmatched young voters of 2024 were less Democratic. Some may be voters whose records the match missed, and some may be respondents who said they voted and did not.

The standard CES weight is proportional to the pre-election weight, and the vote is a post-election item. The post-election weight exists for 2012, 2016 and 2020 and gives age gaps of +19.9, +22.4 and +20.4 (95% CI 17.9 to 22.9), against +18.7, +22.9 and +22.2 with the standard weight. It does not exist for 2024, so the change from 2020 with the post-election weight to 2024 with the standard weight mixes two weights. That change is −5.3 (95% CI −9.4 to −1.2) points, smaller in size than the −7.1 with the standard weight, and its interval excludes zero. The fall among all voters therefore does not depend on this choice, and its size does.

The ANES gives no cleaner reading, because its 2024 sample leans Democratic. Its two-party Democratic share was 54.5% (95% CI 52.3% to 56.7%) against 49.2% in the certified count and 49.0% (95% CI 48.2% to 49.7%) in the CES. The ANES exceeds the count by +5.3 (95% CI 3.0 to 7.5) points, and the CES differs from it by −0.3 (95% CI −1.0 to 0.5). The ANES also exceeded the count in 2020, by +3.5 (95% CI 1.7 to 5.2) points. The excess is largest among voters sixty-five and older, where the ANES share, 57.4% (95% CI 53.7% to 61.1%), is above the CES share by +11.9 (95% CI 8.0 to 15.7) points and above the CES share among matched voters of that age, 46.0% (95% CI 44.8% to 47.2%). It is also positive among voters forty-five to sixty-four, at +7.8 (95% CI 3.8 to 11.9) points. Among voters under thirty the ANES is below the CES by −4.3 (95% CI −12.3 to 3.6) points, an interval that includes zero. The near-zero ANES gap in 2024 therefore comes mostly from its oldest group. No official count gives the vote by age, so which survey is closer within an age group cannot be tested here.

Split by interview mode, the 2024 ANES cells for voters under thirty have effective sample sizes of 86 in the web sample and 31 in the face-to-face sample, below the floor. The ANES therefore cannot show whether the fall depends on mode. In the web sample the gap was +12.8 (95% CI 4.2 to 21.5) in 2012 and +19.3 (95% CI 10.0 to 28.7) in 2016, and in the face-to-face sample it was +21.7 (95% CI 9.2 to 34.3) in 2012 (the second button of Table 3). In 2024 1,884 of the 3,933 two-party voters (48%) are panel or paper cases with no mode weight and fall outside every mode cell, and the 2020 study has no mode weights.

Table 3. Between 2020 and 2024 the CES age gap in the vote changed by −7.1 points among all voters and by −0.6, an interval that includes zero, among matched voters

### Whether the party-identification gap fell by 2024 depends on the baseline wave

Party identification is asked of every respondent, voters or not, and it does not depend on the two candidates of one election, so it offers a check on the vote comparison. Table 4 plots the Democratic share of party identifiers by age group. In the CES the gap between the youngest and oldest groups was between +13.9 and +21.3 points in each of the 10 even-year waves from 2006 to 2024, with every interval above zero, and 2024 is the lowest of the ten. It was +14.9 (95% CI 12.9 to 17.0) in 2020 and +13.9 (95% CI 11.2 to 16.5) in 2024, a change of −1.1 (95% CI −4.4 to 2.3) points that includes zero. The baseline matters. The gap was +17.2 (95% CI 15.1 to 19.3) in 2018, a change to 2024 of −3.3 (95% CI −6.7 to 0.1) points that includes zero, and +21.1 (95% CI 19.0 to 23.3) in 2022, a change to 2024 of −7.3 (95% CI −10.6 to −3.9) points. The ANES gap fell from +14.5 (95% CI 9.2 to 19.8) to +1.9 (95% CI −4.7 to 8.6), a change of −12.6 (95% CI −21.1 to −4.0) points, and the web sample alone gives +1.1 (95% CI −8.9 to 11.2) in 2024, while the face-to-face sample has too few respondents under thirty to publish.

Table 4. Among party identifiers in the CES the youngest group was more Democratic than the oldest in every wave from 2006 to 2024

The CES therefore shows no detectable fall in party identification against 2020 or 2018, and a fall against 2022. The CES gap moved by several points between adjacent waves, so a fall measured against one wave is not a trend. The ANES shows a fall in both the vote and party identification against 2020, from a sample whose oldest group leans Democratic relative to the CES, as the previous section reports. An account in which party attachment strengthens with the years a person has held it gives age a role of its own in party identification [4], and this chapter does not test it.

### Two cohorts' early Democratic leads were smaller by 2024

A birth cohort follows the same group of people as far as a survey can. Table 5 follows each cohort of the ANES cumulative file, in the sixteen-year birth groups that Chapter 2.1, Cohort change in partisan sorting (https://vishalsingh.org/politics/how-the-sort-happened) uses, through the elections in which the cohort has enough voters. It plots the cohort's Democratic share minus the share among voters born in other years in the same election. The subtraction removes anything that moves all voters together in one election, such as a landslide, and it leaves age and the changing make-up of the other voters in place. Cohort cells include every voter with a known cohort, whether or not the age is known.

The cohort born 1975 to 1990 voted 66.0% (95% CI 57.3% to 74.7%) Democratic in 2004, +19.7 (95% CI 10.1 to 29.3) points above other voters, and 55.6% (95% CI 51.3% to 60.0%) in 2024, +1.5 (95% CI −3.7 to 6.6) points above them, a change in its lead of −18.2 (95% CI −29.1 to −7.3) points. The cohort born 1943 to 1958 led by +15.6 (95% CI 10.1 to 21.2) points in 1972 and by +2.7 (95% CI −2.1 to 7.5) in 2024, a change of −12.9 (95% CI −20.3 to −5.5) points (Table 6). The CES, which starts in 2008, shows the same direction for the 1975 to 1990 cohort. Its share fell from 66.3% (95% CI 64.6% to 68.0%) in 2008 to 54.6% (95% CI 53.0% to 56.2%) in 2024, and its lead was +16.6 (95% CI 14.7 to 18.5) points in 2008 and +7.5 (95% CI 5.7 to 9.3) in 2024, a change of −9.1 (95% CI −11.7 to −6.5) points.

Table 5. The cohorts born 1943 to 1958 and 1975 to 1990 began with a Democratic lead over other voters in the ANES and held a smaller one in 2024

The pattern is not general. The cohort born 1927 to 1942 was below other voters in the ANES in every election from 2008 to 2020, and its 2024 lead, +4.6 (95% CI −5.3 to 14.6) points, is above them. Its change between 1956 and 2024 is +2.5 (95% CI −10.2 to 15.1) points, an interval that includes zero. In the CES the same cohort's 2024 lead is −13.9 (95% CI −17.5 to −10.2) points, so the two surveys disagree about the oldest voters, as the 2024 section reports. The cohort born 1911 to 1926 led other voters by +7.8 (95% CI 2.0 to 13.6) points in 1952 and by +6.5 (95% CI −2.4 to 15.3) in 1996, a change of −1.4 (95% CI −11.9 to 9.2) points. That interval does not show a loss of the cohort's lead between 1952 and 1996, and its lower end is close to the change for the 1943 to 1958 cohort. The cohort born 1959 to 1974 began near the average, at +0.6 (95% CI −7.7 to 9.0) points in 1984, and ended below it, at −5.5 (95% CI −10.5 to −0.5) in 2024. In the CES the lead of that cohort changed by −7.3 (95% CI −9.6 to −5.1) points between 2008 and 2024 and the lead of the cohort born 1943 to 1958 by +0.8 (95% CI −1.5 to 3.0). The lead of the cohort born 1991 or later changed by −10.5 (95% CI −21.7 to 0.6) points in the ANES between 2016 and 2024, an interval that includes zero. In the CES it changed by +5.9 (95% CI 0.1 to 11.7) points between 2012 and 2024, from a first cell that holds only voters aged eighteen to twenty-one.

Party identification moves in the CES, where the cohort samples are large. The party-identification leads of 4 of the 5 cohorts changed by more than sampling error between their first and last waves. The changes are −9.6 (95% CI −13.6 to −5.6) points for the cohort born 1927 to 1942, −7.2 (95% CI −9.2 to −5.2) for 1959 to 1974, −4.8 (95% CI −7.2 to −2.4) for 1975 to 1990 and −7.3 (95% CI −13.9 to −0.7) for 1991 or later. The change for the cohort born 1943 to 1958, −1.7 (95% CI −3.8 to 0.3), includes zero. The cohort born 1991 or later therefore lost party-identification lead while its CES vote lead rose, and the two measures do not agree. No ANES cohort's lead in party identification changed by more than sampling error, and those intervals are wide.

Table 6. The vote lead of the 1975 to 1990 cohort over other voters changed by −18.2 points in the ANES between 2004 and 2024 and by −9.1 in the CES between 2008 and 2024

These comparisons follow a cohort, so they mix age with period. A cohort that is more Democratic than other voters when young and closer to them when older fits an age effect, in which people become more like other voters as they age. It fits equally well a cohort effect that fades. It also fits a gap between the first cell, which holds only the cohort's members old enough to vote, and the last cell, which holds all of them, and an election in which the young moved more than the old. Ghitza, Gelman and Auerbach model presidential voting as the cumulative impression of political events, which count most in a voter's teenage and early adult years, and divide voters into five generations [5]. The model needs a measured series of events, the Gallup presidential approval series, and an assumed profile of impressionability by age, and this chapter supplies neither.

### The age gap by gender and race

Table 7 splits the CES age gap by gender and race, pooling 2008 with 2012 and 2020 with 2024 so that every cell clears the floor. The gap among men fell from +27.0 (95% CI 24.1 to 29.8) to +19.9 (95% CI 16.6 to 23.1) points, a change of −7.1 (95% CI −11.4 to −2.8), and the gap among women went from +17.3 (95% CI 14.9 to 19.7) to +16.1 (95% CI 13.4 to 18.7), a change of −1.3 (95% CI −4.9 to 2.3) that includes zero. The gap among women minus the gap among men was −9.6 (95% CI −13.4 to −5.9) points in the earlier period and −3.8 (95% CI −8.0 to 0.4) in the later one, so men's age gap was larger in 2008 and 2012 and is no longer clearly larger. Chapter 3.6, The gender gap in attitudes and votes (https://vishalsingh.org/politics/the-gender-gap) compares women and men within the youngest group of voters, and this chapter compares young and old within each gender.

Race separates the age gaps more than gender does. Among white voters the gap was +20.2 (95% CI 17.7 to 22.7) points in 2020 and 2024 pooled. Among Black voters it was −12.3 (95% CI −17.7 to −6.8) points, so older Black voters were more Democratic than younger Black voters, and the white gap minus the Black gap is +32.5 (95% CI 26.5 to 38.5) points. Among Hispanic voters the gap fell from +22.1 (95% CI 12.9 to 31.2) to +5.3 (95% CI −1.7 to 12.3) points, a change of −16.8 (95% CI −28.3 to −5.2), and the later interval includes zero. Asian voters under thirty are too few to publish a gap for 2008 and 2012, and for 2020 and 2024 pooled the gap is +12.9 (95% CI 2.5 to 23.4) points, from 142 effective respondents under thirty. In 2024 alone the effective sample of Black voters under thirty is 95, below the floor, so the pooled estimates are the ones reported. Chapter 3.3, Hispanic, Black and Asian voters (https://vishalsingh.org/politics/hispanic-black-and-asian-voters; planned) follows how each of these groups voted, and this chapter compares the young and old within each.

Table 7. In 2020 and 2024 the age gap in the vote was +20.2 points among white voters and −12.3 among Black voters

### The estimated age effect depends on which of three assumptions holds

Table 8 estimates the three comparisons as straight-line slopes, in points of Democratic vote share per decade, on voters aged eighteen to seventy-three. In the CES, one decade of age within an election goes with −4.3 (95% CI −4.6 to −4.1) points, one decade of time at a fixed age with −1.2 (95% CI −1.8 to −0.5), and one decade along a cohort with −5.2 (95% CI −5.9 to −4.6). In the ANES the slopes are −2.2 (95% CI −2.6 to −1.7), +1.6 (95% CI 1.3 to 1.9) and +0.3 (95% CI −0.3 to 0.8), and only the first two intervals exclude zero. When the effects are straight lines the third slope equals the sum of the first two. The sum of the first two minus the third is −0.8 (95% CI −1.0 to −0.6) in the ANES and −0.3 (95% CI −0.5 to −0.1) in the CES (bootstrap intervals), and both intervals exclude zero, so the data do not support effects that are exactly straight lines.

Table 8. In the CES the vote moved by −4.3 points per decade of age within an election, −1.2 per decade at a fixed age and −5.2 along a cohort

If the effects are straight lines, each assumption turns these slopes into an age slope. If birth cohorts have no trend, the age slope is the first slope, −4.3 points per decade in the CES. If elections have no trend, the age slope is the third slope, −5.2 in the CES and +0.3 in the ANES. If age has no trend, the age slope is zero, and the whole difference between older and younger voters inside an election is a difference between birth cohorts. The age slope in the ANES therefore runs between −2.2 and +0.3 points per decade depending on the assumption, and in the CES between −5.2 and zero.

A model that gives every age band, election and birth cohort its own effect shows the same dependence in full (Table 9). It is a linear probability model that gives each of 14 four-year age bands, each presidential election and each four-year birth cohort an effect on the Democratic share, fitted to the share in every age-by-election cell. It cannot be estimated without a constraint, because adding a straight line to the age effects and to the cohort effects, and subtracting a straight line from the election effects, leaves every fitted share unchanged. Three constraints, each setting the straight-line trend of one set of effects to zero, give profiles that fit the data identically and differ only by a tilt. The span of a profile is the effect of the oldest band minus the effect of the youngest. It combines the slope with the bends in the profile, so a profile whose age slope is zero still has a span that is not exactly zero. In the CES the span is −22.2 (95% CI −25.0 to −19.2) points if birth cohorts have no trend, −27.3 (95% CI −31.5 to −23.3) if elections have none and +1.0 (95% CI −0.8 to 3.1) if ages have none. In the ANES the three spans are −13.3 (95% CI −18.5 to −8.7), −4.8 (95% CI −10.3 to 0.0) and −3.8 (95% CI −7.8 to −0.2). Where each profile bends is the same under all three constraints and is identified from the data, and the overall slope is not.

Table 9. In the CES the age effect from the youngest to the oldest band is −22.2 points if birth years carry no trend, −27.3 if elections carry none and +1.0 if ages carry none

Which constraint to use is a question for theory, and the data do not settle it. Fosse and Winship review the methods that give a point estimate by adding a restriction, among them equality constraints, Moore-Penrose estimators (the minimum-norm fit used here as the base solution) and multilevel models. They also describe an approach that reports bounds and sensitivity to the restriction instead [6]. This chapter takes the second course. It reports the range of the age effect across three constraints and does not choose among them.

### These shares describe voters

Every vote share here is a share of respondents who reported voting for a major-party candidate, so an age gap in the vote is a gap among voters. It says nothing about the adults who did not vote. Turnout differs by age group, and Chapter 3.1, Turnout (https://vishalsingh.org/politics/turnout) reports it by age and by other characteristics in the Current Population Survey. The gap among voters can change because preferences change or because different people vote, and these surveys cannot separate the two. Chapter 3.2, The two coalitions (https://vishalsingh.org/politics/the-two-coalitions) reports the age make-up of each party's voters. The comparison of matched and unmatched voters above is a reminder that who is counted affects the estimate even among voters.

### What these data cannot show

The surveys interview different people in each election, so a cohort line does not follow anyone. It mixes people who changed, people who joined or left the sample (a cohort is smaller at older ages and its youngest members enter as they turn eighteen), and the effects of age and election. A panel study that re-interviews the same voters separates a person's change from the replacement of cohorts, and it still cannot separate the effect of age from the effect of the election in which the person is re-interviewed. The ANES 2024 Time Series holds a sample interviewed in 2016, 2020 and 2024 and the CES has panel files, but the earlier waves of both are not in the data store, so no panel evidence appears here.

The chapter chooses no constraint for the age-period-cohort model and reports the range. A model with more structure can give a narrower answer only by assuming that structure, and the surveys do not test it. The generation labels in the literature summarize cohort differences, and they do not explain why those differences arise. The data hold no measure of the events, campaigns or candidates that might have shaped any cohort.

The vote is the respondent's report, restricted to two-party voters. The ANES Democratic share exceeds the certified count in 2020 and 2024 by more than its interval, and the excess is largest among voters sixty-five and older. Its age gaps therefore rest on a sample that departs from the count most in the oldest group. The CES share is close to the count in 2024. Neither survey can be checked against an official count by age group. The two surveys disagree about 2024, and the explanations offered here, who is matched to voter records and interview mode, cannot be settled with these files. The ANES youngest-group cells are small, 3 elections have none to publish, 649 two-party voters have no recorded age and fall outside every age cell, and age is top-coded at eighty in 2020 and 2024. The 2012, 2016 and 2024 ANES samples mix modes and 2020 has no mode weights, so a change between those elections can include a change of mode. The CES is an opt-in panel and its intervals leave out how respondents joined it. The ANES intervals ignore clustering and stratification, so they can be too narrow or too wide. The chapter reports many comparisons, and no interval is adjusted for that. Cohorts are sixteen-year groups, and a finer grouping could show movements that these groups average away.

## Tables

### Table 1. The ANES age gap in the Democratic vote was above zero in every election from 2004 to 2020 and included zero in 2024

Democratic share of the two-party presidential vote by age group (18 to 29, 30 to 44, 45 to 64 and 65 and over), ANES 1952 to 2024; 95% intervals

| Interviews | Election | Age group | Democratic share (%) | 95% interval low | 95% interval high | Voters |
| --- | ---: | --- | ---: | ---: | ---: | ---: |
| all | 1952 | 18 to 29 | 42.3 | 35.1 | 49.5 | 182 |
| all | 1956 | 18 to 29 | 42.1 | 34.9 | 49.4 | 178 |
| all | 1960 | 18 to 29 | n/a | n/a | n/a | n/a |
| all | 1964 | 18 to 29 | 72.3 | 65.5 | 79.1 | 166 |
| all | 1968 | 18 to 29 | 44.9 | 36.6 | 53.3 | 138 |
| all | 1972 | 18 to 29 | 47.3 | 42.4 | 52.2 | 402 |
| all | 1976 | 18 to 29 | 52.5 | 46.5 | 58.5 | 272 |
| all | 1980 | 18 to 29 | 41.2 | 33.8 | 48.6 | 170 |
| all | 1984 | 18 to 29 | 43.2 | 37.1 | 49.3 | 257 |
| all | 1988 | 18 to 29 | 47.8 | 40.5 | 55.1 | 182 |
| all | 1992 | 18 to 29 | 63.4 | 56.5 | 70.2 | 192 |
| all | 1996 | 18 to 29 | n/a | n/a | n/a | n/a |
| all | 2000 | 18 to 29 | n/a | n/a | n/a | n/a |
| all | 2004 | 18 to 29 | 66.0 | 57.3 | 74.7 | 137 |
| all | 2008 | 18 to 29 | 67.5 | 59.8 | 75.2 | 222 |
| all | 2012 | 18 to 29 | 62.6 | 56.8 | 68.4 | 501 |
| all | 2016 | 18 to 29 | 61.9 | 54.9 | 68.8 | 299 |
| all | 2020 | 18 to 29 | 69.7 | 64.5 | 74.9 | 588 |
| all | 2024 | 18 to 29 | 56.3 | 48.9 | 63.6 | 285 |
| all | 1952 | 30 to 44 | 46.9 | 42.1 | 51.6 | 429 |
| all | 1956 | 30 to 44 | 41.8 | 37.4 | 46.2 | 486 |
| all | 1960 | 30 to 44 | 51.2 | 44.8 | 57.6 | 327 |
| all | 1964 | 30 to 44 | 68.7 | 64.0 | 73.4 | 377 |
| all | 1968 | 30 to 44 | 52.1 | 46.3 | 58.0 | 282 |
| all | 1972 | 30 to 44 | 34.2 | 29.6 | 38.8 | 415 |
| all | 1976 | 30 to 44 | 48.5 | 43.2 | 53.9 | 352 |
| all | 1980 | 30 to 44 | 41.3 | 35.3 | 47.3 | 259 |
| all | 1984 | 30 to 44 | 40.7 | 36.3 | 45.1 | 482 |
| all | 1988 | 30 to 44 | 46.4 | 41.7 | 51.1 | 433 |
| all | 1992 | 30 to 44 | 56.1 | 51.6 | 60.6 | 474 |
| all | 1996 | 30 to 44 | 54.0 | 48.3 | 59.6 | 352 |
| all | 2000 | 30 to 44 | 46.2 | 40.5 | 51.9 | 354 |
| all | 2004 | 30 to 44 | 44.5 | 37.1 | 52.0 | 196 |
| all | 2008 | 30 to 44 | 58.4 | 52.4 | 64.5 | 411 |
| all | 2012 | 30 to 44 | 55.7 | 51.4 | 59.9 | 904 |
| all | 2016 | 30 to 44 | 61.9 | 57.3 | 66.6 | 568 |
| all | 2020 | 30 to 44 | 58.8 | 55.4 | 62.3 | 1,373 |
| all | 2024 | 30 to 44 | 55.0 | 50.3 | 59.6 | 841 |
| all | 1952 | 45 to 64 | 38.8 | 34.0 | 43.5 | 405 |
| all | 1956 | 45 to 64 | 36.6 | 32.1 | 41.2 | 434 |
| all | 1960 | 45 to 64 | 50.2 | 44.1 | 56.2 | 356 |
| all | 1964 | 45 to 64 | 69.1 | 64.6 | 73.6 | 408 |
| all | 1968 | 45 to 64 | 42.4 | 37.1 | 47.7 | 335 |
| all | 1972 | 45 to 64 | 29.8 | 25.9 | 33.7 | 527 |
| all | 1976 | 45 to 64 | 53.3 | 48.5 | 58.0 | 445 |
| all | 1980 | 45 to 64 | 46.1 | 40.2 | 52.1 | 271 |
| all | 1984 | 45 to 64 | 41.7 | 36.8 | 46.6 | 391 |
| all | 1988 | 45 to 64 | 47.2 | 42.0 | 52.5 | 345 |
| all | 1992 | 45 to 64 | 57.5 | 52.6 | 62.3 | 395 |
| all | 1996 | 45 to 64 | 59.2 | 53.4 | 65.0 | 331 |
| all | 2000 | 45 to 64 | 53.1 | 47.8 | 58.4 | 416 |
| all | 2004 | 45 to 64 | 45.0 | 39.1 | 50.9 | 332 |
| all | 2008 | 45 to 64 | 52.3 | 47.3 | 57.2 | 591 |
| all | 2012 | 45 to 64 | 52.3 | 49.2 | 55.4 | 1,760 |
| all | 2016 | 45 to 64 | 48.4 | 44.7 | 52.2 | 976 |
| all | 2020 | 45 to 64 | 50.6 | 47.6 | 53.6 | 2,014 |
| all | 2024 | 45 to 64 | 51.8 | 47.9 | 55.7 | 1,236 |
| all | 1952 | 65 and over | 36.7 | 28.9 | 44.4 | 150 |
| all | 1956 | 65 and over | 43.9 | 35.9 | 51.9 | 148 |
| all | 1960 | 65 and over | 39.2 | 29.9 | 48.4 | 148 |
| all | 1964 | 65 and over | 55.3 | 47.6 | 63.1 | 159 |
| all | 1968 | 65 and over | 45.1 | 37.2 | 53.0 | 153 |
| all | 1972 | 65 and over | 31.9 | 25.9 | 37.9 | 235 |
| all | 1976 | 65 and over | 49.4 | 43.0 | 55.8 | 245 |
| all | 1980 | 65 and over | 46.3 | 38.9 | 53.7 | 175 |
| all | 1984 | 65 and over | 42.9 | 36.5 | 49.3 | 233 |
| all | 1988 | 65 and over | 47.9 | 41.4 | 54.3 | 234 |
| all | 1992 | 65 and over | 60.4 | 54.8 | 66.0 | 296 |
| all | 1996 | 65 and over | 60.6 | 54.0 | 67.3 | 248 |
| all | 2000 | 65 and over | 54.2 | 47.0 | 61.4 | 228 |
| all | 2004 | 65 and over | 52.1 | 43.2 | 61.0 | 146 |
| all | 2008 | 65 and over | 44.9 | 37.9 | 52.0 | 294 |
| all | 2012 | 65 and over | 46.9 | 42.7 | 51.0 | 983 |
| all | 2016 | 65 and over | 46.4 | 41.9 | 50.8 | 679 |
| all | 2020 | 65 and over | 52.7 | 49.6 | 55.8 | 1,883 |
| all | 2024 | 65 and over | 57.4 | 53.7 | 61.1 | 1,390 |
| ftf | 2012 | 18 to 29 | 63.2 | 53.8 | 72.6 | 225 |
| ftf | 2012 | 30 to 44 | 58.0 | 51.0 | 65.0 | 376 |
| ftf | 2016 | 30 to 44 | 68.4 | 59.7 | 77.2 | 144 |
| ftf | 2012 | 45 to 64 | 51.7 | 45.6 | 57.9 | 474 |
| ftf | 2016 | 45 to 64 | 51.0 | 43.8 | 58.3 | 281 |
| ftf | 2024 | 45 to 64 | 45.8 | 37.0 | 54.7 | 224 |
| ftf | 2012 | 65 and over | 41.5 | 33.1 | 49.9 | 221 |
| ftf | 2016 | 65 and over | 45.2 | 36.9 | 53.5 | 216 |
| ftf | 2024 | 65 and over | 54.9 | 46.6 | 63.2 | 255 |
| web | 2012 | 18 to 29 | 62.3 | 55.0 | 69.6 | 276 |
| web | 2016 | 18 to 29 | 66.7 | 58.9 | 74.5 | 210 |
| web | 2012 | 30 to 44 | 54.4 | 49.1 | 59.7 | 528 |
| web | 2016 | 30 to 44 | 59.7 | 54.3 | 65.1 | 426 |
| web | 2024 | 30 to 44 | 55.4 | 48.4 | 62.4 | 314 |
| web | 2012 | 45 to 64 | 52.6 | 49.0 | 56.1 | 1,286 |
| web | 2016 | 45 to 64 | 47.6 | 43.3 | 51.9 | 703 |
| web | 2024 | 45 to 64 | 57.6 | 51.3 | 63.9 | 410 |
| web | 2012 | 65 and over | 49.5 | 44.8 | 54.1 | 762 |
| web | 2016 | 65 and over | 47.4 | 42.3 | 52.5 | 473 |
| web | 2024 | 65 and over | 59.8 | 53.4 | 66.2 | 407 |

Views: All interviews (mode = all); Face to face (mode = ftf); Web (mode = web).

Note: A cell is plotted only when it has 100 or more respondents and a Kish effective sample size (the sample size after weighting) of 100 or more, the floor of this chapter. A blank cell leaves a gap in the line. The youngest group falls below the floor in 3 elections (1960, 1996 and 2000).

Note: The mode views use the face-to-face weight on face-to-face respondents and the web weight on web respondents. The 2020 study has no interview-mode weights and no in-person interviews, so the mode views leave 2020 open, and many youngest-group cells fall below the floor within a mode.

Note: Age is top-coded at 80 in the 2020 and 2024 files, 649 two-party voters with no recorded age are outside every cell, and respondents under 18 (a handful in the file) are left out. Intervals are model based: they treat the weighted sample as a simple random sample and ignore clustering and stratification.

Source: ANES Cumulative Data File, presidential elections 1952-2024; weighted (post-election weight where the file has one, otherwise VCF0009z); two-party presidential voters

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/vote_by_age_anes.json

### Table 2. In every CES election from 2008 to 2020 the Democratic share was lower among voters forty-five to sixty-four than among voters thirty to forty-four, and lower again among voters sixty-five and older

Democratic share of the two-party presidential vote by age band (18 to 24, 25 to 29, 30 to 44, 45 to 64 and 65 and over), CES 2008 to 2024; 95% intervals

| Weight | Election | Age band | Democratic share (%) | 95% interval low | 95% interval high | Voters |
| --- | ---: | --- | ---: | ---: | ---: | ---: |
| standard | 2008 | 18 to 24 | 69.3 | 66.5 | 72.1 | 1,641 |
| standard | 2012 | 18 to 24 | 62.2 | 58.8 | 65.6 | 1,633 |
| standard | 2016 | 18 to 24 | 67.7 | 64.8 | 70.7 | 1,569 |
| standard | 2020 | 18 to 24 | 70.5 | 67.6 | 73.4 | 1,795 |
| standard | 2024 | 18 to 24 | 63.4 | 58.7 | 68.2 | 1,478 |
| standard | 2008 | 25 to 29 | 64.3 | 61.7 | 67.0 | 1,686 |
| standard | 2012 | 25 to 29 | 61.7 | 58.4 | 65.0 | 1,919 |
| standard | 2016 | 25 to 29 | 64.0 | 61.5 | 66.6 | 2,449 |
| standard | 2020 | 25 to 29 | 65.9 | 63.4 | 68.5 | 2,565 |
| standard | 2024 | 25 to 29 | 58.5 | 54.5 | 62.4 | 1,604 |
| standard | 2008 | 30 to 44 | 56.4 | 54.9 | 57.9 | 5,702 |
| standard | 2012 | 30 to 44 | 58.8 | 56.9 | 60.7 | 4,370 |
| standard | 2016 | 30 to 44 | 57.5 | 56.2 | 58.9 | 8,868 |
| standard | 2020 | 30 to 44 | 61.5 | 60.2 | 62.7 | 9,870 |
| standard | 2024 | 30 to 44 | 55.1 | 53.5 | 56.8 | 7,073 |
| standard | 2008 | 45 to 64 | 50.6 | 49.4 | 51.7 | 10,079 |
| standard | 2012 | 45 to 64 | 51.3 | 50.3 | 52.2 | 18,715 |
| standard | 2016 | 45 to 64 | 47.4 | 46.5 | 48.3 | 18,133 |
| standard | 2020 | 45 to 64 | 49.2 | 48.3 | 50.2 | 17,747 |
| standard | 2024 | 45 to 64 | 43.9 | 42.8 | 45.1 | 16,848 |
| standard | 2008 | 65 and over | 42.7 | 41.0 | 44.5 | 4,477 |
| standard | 2012 | 65 and over | 43.2 | 41.9 | 44.6 | 11,152 |
| standard | 2016 | 65 and over | 42.8 | 41.3 | 44.3 | 9,872 |
| standard | 2020 | 65 and over | 45.6 | 44.4 | 46.8 | 11,895 |
| standard | 2024 | 65 and over | 45.5 | 44.4 | 46.7 | 15,005 |
| validated | 2020 | 18 to 24 | 70.4 | 67.0 | 73.9 | 1,180 |
| validated | 2024 | 18 to 24 | 68.7 | 62.9 | 74.6 | 530 |
| validated | 2020 | 25 to 29 | 67.9 | 64.8 | 70.9 | 1,736 |
| validated | 2024 | 25 to 29 | 62.3 | 57.5 | 67.0 | 873 |
| validated | 2020 | 30 to 44 | 62.8 | 61.4 | 64.1 | 7,532 |
| validated | 2024 | 30 to 44 | 57.0 | 55.2 | 58.7 | 5,208 |
| validated | 2020 | 45 to 64 | 48.7 | 47.7 | 49.7 | 14,897 |
| validated | 2024 | 45 to 64 | 45.9 | 44.8 | 47.0 | 13,637 |
| validated | 2020 | 65 and over | 46.1 | 44.8 | 47.4 | 10,401 |
| validated | 2024 | 65 and over | 41.6 | 40.4 | 42.9 | 12,700 |

Views: Standard weight, all voters (weight = standard); Validated-voter weight, matched voters (weight = validated).

Note: The CES holds far more young voters than the ANES, so no cell falls below the floor. The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel.

Note: Intervals are model based: they treat the weighted sample as a simple random sample and ignore clustering and stratification.

Source: CES Cumulative File, presidential elections 2008-2024; weighted (weight_cumulative); two-party presidential voters

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/vote_by_age_ces.json

### Table 3. Between 2020 and 2024 the CES age gap in the vote changed by −7.1 points among all voters and by −0.6, an interval that includes zero, among matched voters

Democratic share of two-party voters aged 18 to 29 minus the share among voters aged 65 and over, ANES 1952 to 2024 and CES 2008 to 2024; 95% intervals

| Measure | Survey and weight | Year | Gap (points) | 95% interval low | 95% interval high | Respondents in the two groups |
| --- | --- | ---: | ---: | ---: | ---: | ---: |
| vote | ANES | 1952 | +5.6 | −4.9 | +16.2 | 332 |
| vote | ANES | 1956 | −1.8 | −12.6 | +9.0 | 326 |
| vote | ANES | 1960 | n/a | n/a | n/a | n/a |
| vote | ANES | 1964 | +16.9 | +6.6 | +27.3 | 325 |
| vote | ANES | 1968 | −0.2 | −11.7 | +11.3 | 291 |
| vote | ANES | 1972 | +15.3 | +7.6 | +23.1 | 637 |
| vote | ANES | 1976 | +3.1 | −5.7 | +11.9 | 517 |
| vote | ANES | 1980 | −5.1 | −15.6 | +5.4 | 345 |
| vote | ANES | 1984 | +0.3 | −8.5 | +9.1 | 490 |
| vote | ANES | 1988 | −0.1 | −9.8 | +9.6 | 416 |
| vote | ANES | 1992 | +2.9 | −5.9 | +11.8 | 488 |
| vote | ANES | 1996 | n/a | n/a | n/a | n/a |
| vote | ANES | 2000 | n/a | n/a | n/a | n/a |
| vote | ANES | 2004 | +13.9 | +1.4 | +26.3 | 283 |
| vote | ANES | 2008 | +22.6 | +12.2 | +33.0 | 516 |
| vote | ANES | 2012 | +15.7 | +8.6 | +22.8 | 1,484 |
| vote | ANES | 2016 | +15.5 | +7.2 | +23.7 | 978 |
| vote | ANES | 2020 | +17.0 | +11.0 | +23.1 | 2,471 |
| vote | ANES | 2024 | −1.1 | −9.4 | +7.1 | 1,675 |
| vote | CES | 2008 | +24.5 | +21.8 | +27.1 | 7,804 |
| vote | CES | 2012 | +18.7 | +16.0 | +21.4 | 14,704 |
| vote | CES | 2016 | +22.9 | +20.4 | +25.3 | 13,890 |
| vote | CES | 2020 | +22.2 | +19.9 | +24.4 | 16,255 |
| vote | CES | 2024 | +15.0 | +11.8 | +18.3 | 18,087 |
| vote | CES, matched voters, validated-voter weight | 2020 | +22.8 | +20.1 | +25.4 | 13,317 |
| vote | CES, matched voters, validated-voter weight | 2024 | +23.0 | +19.1 | +26.9 | 14,103 |
| mode | ANES, all interviews | 2008 | +22.6 | +12.2 | +33.0 | 516 |
| mode | ANES, all interviews | 2012 | +15.7 | +8.6 | +22.8 | 1,484 |
| mode | ANES, all interviews | 2016 | +15.5 | +7.2 | +23.7 | 978 |
| mode | ANES, all interviews | 2020 | +17.0 | +11.0 | +23.1 | 2,471 |
| mode | ANES, all interviews | 2024 | −1.1 | −9.4 | +7.1 | 1,675 |
| mode | ANES, face to face | 2012 | +21.7 | +9.2 | +34.3 | 446 |
| mode | ANES, web | 2012 | +12.8 | +4.2 | +21.5 | 1,038 |
| mode | ANES, web | 2016 | +19.3 | +10.0 | +28.7 | 683 |
| weight | CES, standard weight | 2008 | +24.5 | +21.8 | +27.1 | 7,804 |
| weight | CES, standard weight | 2012 | +18.7 | +16.0 | +21.4 | 14,704 |
| weight | CES, standard weight | 2016 | +22.9 | +20.4 | +25.3 | 13,890 |
| weight | CES, standard weight | 2020 | +22.2 | +19.9 | +24.4 | 16,255 |
| weight | CES, standard weight | 2024 | +15.0 | +11.8 | +18.3 | 18,087 |
| weight | CES, post-election weight | 2012 | +19.9 | +17.2 | +22.6 | 14,704 |
| weight | CES, post-election weight | 2016 | +22.4 | +19.7 | +25.0 | 13,890 |
| weight | CES, post-election weight | 2020 | +20.4 | +17.9 | +22.9 | 16,254 |
| weight | CES, matched voters, validated-voter weight | 2020 | +22.8 | +20.1 | +25.4 | 13,317 |
| weight | CES, matched voters, validated-voter weight | 2024 | +23.0 | +19.1 | +26.9 | 14,103 |
| pid | ANES | 1952 | +10.2 | +1.4 | +19.0 | 486 |
| pid | ANES | 1956 | +8.5 | −0.9 | +18.0 | 438 |
| pid | ANES | 1960 | n/a | n/a | n/a | n/a |
| pid | ANES | 1964 | +17.7 | +9.0 | +26.3 | 472 |
| pid | ANES | 1968 | +0.2 | −8.6 | +9.1 | 469 |
| pid | ANES | 1972 | +7.5 | +1.2 | +13.8 | 973 |
| pid | ANES | 1976 | +7.1 | +0.3 | +13.9 | 825 |
| pid | ANES | 1980 | −2.6 | −10.6 | +5.4 | 588 |
| pid | ANES | 1984 | +4.8 | −2.1 | +11.7 | 815 |
| pid | ANES | 1988 | −5.3 | −12.6 | +2.1 | 704 |
| pid | ANES | 1992 | −6.1 | −12.8 | +0.7 | 832 |
| pid | ANES | 1996 | +0.6 | −8.6 | +9.8 | 548 |
| pid | ANES | 2000 | +1.7 | −7.8 | +11.1 | 505 |
| pid | ANES | 2004 | +8.9 | −1.8 | +19.6 | 393 |
| pid | ANES | 2008 | +13.1 | +4.1 | +22.0 | 711 |
| pid | ANES | 2012 | +7.0 | +0.9 | +13.2 | 1,853 |
| pid | ANES | 2016 | +10.2 | +3.8 | +16.6 | 1,395 |
| pid | ANES | 2020 | +14.5 | +9.2 | +19.8 | 2,883 |
| pid | ANES | 2024 | +1.9 | −4.7 | +8.6 | 2,110 |
| pid | CES | 2006 | +16.3 | +14.2 | +18.4 | 9,392 |
| pid | CES | 2008 | +19.9 | +17.6 | +22.3 | 9,848 |
| pid | CES | 2010 | +21.3 | +18.7 | +23.9 | 15,016 |
| pid | CES | 2012 | +17.5 | +15.2 | +19.7 | 17,855 |
| pid | CES | 2014 | +14.5 | +12.1 | +16.9 | 17,157 |
| pid | CES | 2016 | +14.3 | +12.3 | +16.4 | 18,625 |
| pid | CES | 2018 | +17.2 | +15.1 | +19.3 | 20,577 |
| pid | CES | 2020 | +14.9 | +12.9 | +17.0 | 20,364 |
| pid | CES | 2022 | +21.1 | +19.0 | +23.3 | 20,148 |
| pid | CES | 2024 | +13.9 | +11.2 | +16.5 | 22,842 |

Views: Vote (group = vote); CES vote by weight (group = weight); ANES vote by interview mode (group = mode); Party identification (group = pid).

Note: A cell is plotted only when it has 100 or more respondents and a Kish effective sample size (the sample size after weighting) of 100 or more, the floor of this chapter. A blank cell leaves a gap in the line. Three ANES elections (1960, 1996 and 2000) have too few voters under thirty for a published gap and show a break in the line.

Note: The matched-voter series uses voters with a validated-voter weight, the CES weight for voters whose registration was matched to voter-file records (validated registered voters), which exists for 2018 to 2024 in the file. In 2020 it is a constant multiple of the standard weight. The post-election weight exists for 2012, 2016 and 2020.

Note: In the mode view the face-to-face gap for 2016 and the face-to-face and web gaps for 2024 fall below the floor and are not drawn. The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel.

Source: ANES Cumulative Data File, presidential elections 1952-2024; weighted (post-election weight where the file has one, otherwise VCF0009z); two-party presidential voters; CES weighted (weight_cumulative; vvweight for the matched-voter series)

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/age_gap.json

### Table 4. Among party identifiers in the CES the youngest group was more Democratic than the oldest in every wave from 2006 to 2024

Democratic share of party identifiers (leaners included) by age group, CES even-year waves 2006 to 2024; the ANES view covers presidential-election years 1952 to 2024; 95% intervals

| Survey | Year | Age group | Democratic share (%) | 95% interval low | 95% interval high | Identifiers |
| --- | ---: | --- | ---: | ---: | ---: | ---: |
| ces | 2006 | 18 to 29 | 63.9 | 62.3 | 65.5 | 3,805 |
| ces | 2008 | 18 to 29 | 67.1 | 65.4 | 68.8 | 4,827 |
| ces | 2010 | 18 to 29 | 63.9 | 61.8 | 65.9 | 4,218 |
| ces | 2012 | 18 to 29 | 65.8 | 64.0 | 67.7 | 6,229 |
| ces | 2014 | 18 to 29 | 59.1 | 57.4 | 60.8 | 7,389 |
| ces | 2016 | 18 to 29 | 62.8 | 61.5 | 64.2 | 8,667 |
| ces | 2018 | 18 to 29 | 61.9 | 60.3 | 63.5 | 9,327 |
| ces | 2020 | 18 to 29 | 60.3 | 58.7 | 61.9 | 8,824 |
| ces | 2022 | 18 to 29 | 63.8 | 62.1 | 65.5 | 7,083 |
| ces | 2024 | 18 to 29 | 60.3 | 57.9 | 62.7 | 7,167 |
| ces | 2006 | 30 to 44 | 52.7 | 51.6 | 53.9 | 8,096 |
| ces | 2008 | 30 to 44 | 58.2 | 56.8 | 59.6 | 7,118 |
| ces | 2010 | 30 to 44 | 56.5 | 55.0 | 58.0 | 8,104 |
| ces | 2012 | 30 to 44 | 63.6 | 62.0 | 65.2 | 6,253 |
| ces | 2014 | 30 to 44 | 57.3 | 55.8 | 58.8 | 7,695 |
| ces | 2016 | 30 to 44 | 60.7 | 59.6 | 61.8 | 13,395 |
| ces | 2018 | 30 to 44 | 60.2 | 59.0 | 61.5 | 11,724 |
| ces | 2020 | 30 to 44 | 59.2 | 58.0 | 60.4 | 11,969 |
| ces | 2022 | 30 to 44 | 59.6 | 58.3 | 60.9 | 11,526 |
| ces | 2024 | 30 to 44 | 57.8 | 56.2 | 59.4 | 9,128 |
| ces | 2006 | 45 to 64 | 50.1 | 49.2 | 51.0 | 14,304 |
| ces | 2008 | 45 to 64 | 53.8 | 52.7 | 54.9 | 11,634 |
| ces | 2010 | 45 to 64 | 52.5 | 51.6 | 53.4 | 24,741 |
| ces | 2012 | 45 to 64 | 56.0 | 55.1 | 56.9 | 21,739 |
| ces | 2014 | 45 to 64 | 51.5 | 50.5 | 52.5 | 19,924 |
| ces | 2016 | 45 to 64 | 52.6 | 51.7 | 53.5 | 19,966 |
| ces | 2018 | 45 to 64 | 50.2 | 49.1 | 51.2 | 17,026 |
| ces | 2020 | 45 to 64 | 49.6 | 48.6 | 50.6 | 17,436 |
| ces | 2022 | 45 to 64 | 48.8 | 47.8 | 49.8 | 17,846 |
| ces | 2024 | 45 to 64 | 45.4 | 44.2 | 46.5 | 18,877 |
| ces | 2006 | 65 and over | 47.6 | 46.2 | 49.0 | 5,587 |
| ces | 2008 | 65 and over | 47.2 | 45.5 | 48.9 | 5,021 |
| ces | 2010 | 65 and over | 42.6 | 40.9 | 44.2 | 10,798 |
| ces | 2012 | 65 and over | 48.4 | 47.0 | 49.7 | 11,626 |
| ces | 2014 | 65 and over | 44.6 | 42.9 | 46.3 | 9,768 |
| ces | 2016 | 65 and over | 48.5 | 47.0 | 50.0 | 9,958 |
| ces | 2018 | 65 and over | 44.7 | 43.4 | 46.1 | 11,250 |
| ces | 2020 | 65 and over | 45.3 | 44.0 | 46.6 | 11,540 |
| ces | 2022 | 65 and over | 42.6 | 41.4 | 43.9 | 13,065 |
| ces | 2024 | 65 and over | 46.4 | 45.2 | 47.6 | 15,675 |
| anes | 1952 | 18 to 29 | 65.1 | 59.6 | 70.7 | 284 |
| anes | 1956 | 18 to 29 | 60.8 | 54.8 | 66.7 | 260 |
| anes | 1960 | 18 to 29 | n/a | n/a | n/a | n/a |
| anes | 1964 | 18 to 29 | 70.9 | 65.3 | 76.5 | 254 |
| anes | 1968 | 18 to 29 | 61.7 | 55.4 | 68.0 | 230 |
| anes | 1972 | 18 to 29 | 63.0 | 59.1 | 66.9 | 589 |
| anes | 1976 | 18 to 29 | 65.1 | 60.7 | 69.5 | 461 |
| anes | 1980 | 18 to 29 | 59.8 | 54.5 | 65.0 | 333 |
| anes | 1984 | 18 to 29 | 56.3 | 51.8 | 60.9 | 458 |
| anes | 1988 | 18 to 29 | 50.7 | 45.6 | 55.7 | 375 |
| anes | 1992 | 18 to 29 | 54.4 | 49.5 | 59.3 | 399 |
| anes | 1996 | 18 to 29 | 60.1 | 53.1 | 67.2 | 225 |
| anes | 2000 | 18 to 29 | 61.7 | 54.6 | 68.8 | 225 |
| anes | 2004 | 18 to 29 | 66.4 | 59.3 | 73.5 | 212 |
| anes | 2008 | 18 to 29 | 66.1 | 59.7 | 72.4 | 342 |
| anes | 2012 | 18 to 29 | 57.5 | 52.7 | 62.2 | 774 |
| anes | 2016 | 18 to 29 | 59.9 | 54.9 | 64.9 | 540 |
| anes | 2020 | 18 to 29 | 63.9 | 59.4 | 68.4 | 841 |
| anes | 2024 | 18 to 29 | 55.9 | 50.3 | 61.6 | 493 |
| anes | 1952 | 30 to 44 | 67.4 | 63.6 | 71.2 | 589 |
| anes | 1956 | 30 to 44 | 61.4 | 57.4 | 65.3 | 590 |
| anes | 1960 | 30 to 44 | 62.4 | 56.6 | 68.3 | 363 |
| anes | 1964 | 30 to 44 | 68.2 | 63.9 | 72.6 | 444 |
| anes | 1968 | 30 to 44 | 65.5 | 60.8 | 70.1 | 411 |
| anes | 1972 | 30 to 44 | 58.9 | 54.9 | 63.0 | 565 |
| anes | 1976 | 30 to 44 | 58.9 | 54.2 | 63.5 | 453 |
| anes | 1980 | 30 to 44 | 61.8 | 57.0 | 66.7 | 380 |
| anes | 1984 | 30 to 44 | 50.7 | 46.7 | 54.6 | 606 |
| anes | 1988 | 30 to 44 | 52.5 | 48.5 | 56.4 | 612 |
| anes | 1992 | 30 to 44 | 56.0 | 52.4 | 59.6 | 748 |
| anes | 1996 | 30 to 44 | 55.9 | 51.3 | 60.4 | 548 |
| anes | 2000 | 30 to 44 | 53.0 | 48.3 | 57.7 | 519 |
| anes | 2004 | 30 to 44 | 49.8 | 43.4 | 56.2 | 273 |
| anes | 2008 | 30 to 44 | 58.4 | 53.1 | 63.8 | 540 |
| anes | 2012 | 30 to 44 | 55.0 | 51.3 | 58.8 | 1,142 |
| anes | 2016 | 30 to 44 | 60.5 | 56.7 | 64.4 | 876 |
| anes | 2020 | 30 to 44 | 55.3 | 52.3 | 58.3 | 1,739 |
| anes | 2024 | 30 to 44 | 51.7 | 47.6 | 55.7 | 1,190 |
| anes | 1952 | 45 to 64 | 58.4 | 54.1 | 62.7 | 510 |
| anes | 1956 | 45 to 64 | 52.0 | 47.6 | 56.5 | 488 |
| anes | 1960 | 45 to 64 | 57.4 | 51.6 | 63.1 | 388 |
| anes | 1964 | 45 to 64 | 69.5 | 65.4 | 73.6 | 495 |
| anes | 1968 | 45 to 64 | 61.6 | 57.2 | 65.9 | 484 |
| anes | 1972 | 45 to 64 | 60.9 | 57.4 | 64.4 | 739 |
| anes | 1976 | 45 to 64 | 60.9 | 56.9 | 65.0 | 588 |
| anes | 1980 | 45 to 64 | 61.9 | 57.1 | 66.7 | 399 |
| anes | 1984 | 45 to 64 | 59.8 | 55.5 | 64.0 | 507 |
| anes | 1988 | 45 to 64 | 55.5 | 50.9 | 60.0 | 456 |
| anes | 1992 | 45 to 64 | 57.6 | 53.5 | 61.6 | 574 |
| anes | 1996 | 45 to 64 | 56.4 | 51.4 | 61.4 | 451 |
| anes | 2000 | 45 to 64 | 58.0 | 53.4 | 62.6 | 536 |
| anes | 2004 | 45 to 64 | 50.9 | 45.6 | 56.2 | 408 |
| anes | 2008 | 45 to 64 | 55.6 | 51.2 | 60.1 | 730 |
| anes | 2012 | 45 to 64 | 53.6 | 50.7 | 56.5 | 2,052 |
| anes | 2016 | 45 to 64 | 49.5 | 46.3 | 52.7 | 1,306 |
| anes | 2020 | 45 to 64 | 47.5 | 44.9 | 50.1 | 2,399 |
| anes | 2024 | 45 to 64 | 48.9 | 45.3 | 52.4 | 1,559 |
| anes | 1952 | 65 and over | 55.0 | 48.1 | 61.8 | 202 |
| anes | 1956 | 65 and over | 52.2 | 44.9 | 59.6 | 178 |
| anes | 1960 | 65 and over | 49.6 | 41.2 | 58.1 | 184 |
| anes | 1964 | 65 and over | 53.2 | 46.6 | 59.8 | 218 |
| anes | 1968 | 65 and over | 61.5 | 55.3 | 67.7 | 239 |
| anes | 1972 | 65 and over | 55.5 | 50.5 | 60.4 | 384 |
| anes | 1976 | 65 and over | 57.9 | 52.8 | 63.1 | 364 |
| anes | 1980 | 65 and over | 62.4 | 56.4 | 68.3 | 255 |
| anes | 1984 | 65 and over | 51.5 | 46.3 | 56.7 | 357 |
| anes | 1988 | 65 and over | 55.9 | 50.6 | 61.3 | 329 |
| anes | 1992 | 65 and over | 60.5 | 55.9 | 65.1 | 433 |
| anes | 1996 | 65 and over | 59.5 | 53.7 | 65.3 | 323 |
| anes | 2000 | 65 and over | 60.0 | 53.7 | 66.3 | 280 |
| anes | 2004 | 65 and over | 57.5 | 49.5 | 65.5 | 181 |
| anes | 2008 | 65 and over | 53.0 | 46.7 | 59.3 | 369 |
| anes | 2012 | 65 and over | 50.4 | 46.5 | 54.4 | 1,079 |
| anes | 2016 | 65 and over | 49.7 | 45.8 | 53.7 | 855 |
| anes | 2020 | 65 and over | 49.4 | 46.5 | 52.3 | 2,042 |
| anes | 2024 | 65 and over | 54.0 | 50.5 | 57.5 | 1,617 |

Views: CES (survey = ces); ANES (survey = anes).

Note: A cell is plotted only when it has 100 or more respondents and a Kish effective sample size (the sample size after weighting) of 100 or more, the floor of this chapter. A blank cell leaves a gap in the line. Party identification counts Democrats and Republicans with leaners included and leaves out pure independents.

Note: The ANES estimates for 2012, 2016 and 2024 mix face-to-face and web interviews and the 2020 study has no interview-mode weights. In 2024 the web sample alone gives a gap of +1.1.

Note: The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel. Intervals are model based: they treat the weighted sample as a simple random sample and ignore clustering and stratification.

Source: CES Cumulative File, even-year waves 2006-2024; weighted (weight_cumulative); party identifiers, leaners included; the ANES view: ANES Cumulative Data File, presidential-election years 1952-2024; weighted (VCF0009z); party identifiers, leaners included

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/pid_by_age.json

### Table 5. The cohorts born 1943 to 1958 and 1975 to 1990 began with a Democratic lead over other voters in the ANES and held a smaller one in 2024

Democratic share of the two-party presidential vote among voters in each birth cohort minus the share among voters born in other years, points, ANES 1952 to 2024; 95% intervals; the buttons switch survey and measure

| Survey | Birth cohort | Election | Democratic share (%) | 95% interval low | 95% interval high | Lead over other voters (points) | 95% interval low (lead) | 95% interval high (lead) | Voters |
| --- | --- | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: |
| anes | Born 1895 to 1910 | 1952 | 38.9 | 33.9 | 43.8 | −4.6 | −10.7 | +1.4 | 373 |
| anes | Born 1895 to 1910 | 1956 | 39.3 | 34.2 | 44.4 | −1.4 | −7.5 | +4.6 | 354 |
| anes | Born 1895 to 1910 | 1960 | 49.5 | 42.4 | 56.6 | +0.4 | −8.1 | +8.9 | 261 |
| anes | Born 1895 to 1910 | 1964 | 65.9 | 60.1 | 71.7 | −2.1 | −8.6 | +4.5 | 261 |
| anes | Born 1895 to 1910 | 1968 | 46.1 | 39.0 | 53.2 | −0.2 | −8.2 | +7.7 | 191 |
| anes | Born 1895 to 1910 | 1972 | 32.0 | 26.3 | 37.8 | −4.5 | −10.8 | +1.9 | 253 |
| anes | Born 1895 to 1910 | 1976 | 52.3 | 45.2 | 59.3 | +1.4 | −6.3 | +9.0 | 202 |
| anes | Born 1895 to 1910 | 1980 | 50.0 | 40.2 | 59.8 | +7.1 | −3.3 | +17.4 | 102 |
| anes | Born 1911 to 1926 | 1952 | 46.8 | 42.2 | 51.4 | +7.8 | +2.0 | +13.6 | 453 |
| anes | Born 1911 to 1926 | 1956 | 41.1 | 36.8 | 45.3 | +1.4 | −4.2 | +6.9 | 516 |
| anes | Born 1911 to 1926 | 1960 | 51.2 | 45.2 | 57.1 | +3.3 | −4.6 | +11.1 | 372 |
| anes | Born 1911 to 1926 | 1964 | 68.6 | 64.0 | 73.1 | +1.7 | −4.0 | +7.4 | 401 |
| anes | Born 1911 to 1926 | 1968 | 43.1 | 37.6 | 48.6 | −4.8 | −11.6 | +2.0 | 313 |
| anes | Born 1911 to 1926 | 1972 | 29.6 | 25.3 | 33.9 | −8.4 | −13.6 | −3.3 | 432 |
| anes | Born 1911 to 1926 | 1976 | 53.1 | 47.9 | 58.4 | +2.7 | −3.4 | +8.9 | 363 |
| anes | Born 1911 to 1926 | 1980 | 46.9 | 40.3 | 53.4 | +4.2 | −3.4 | +11.7 | 224 |
| anes | Born 1911 to 1926 | 1984 | 44.4 | 38.5 | 50.2 | +3.2 | −3.4 | +9.8 | 275 |
| anes | Born 1911 to 1926 | 1988 | 44.3 | 37.8 | 50.8 | −3.5 | −10.7 | +3.7 | 228 |
| anes | Born 1911 to 1926 | 1992 | 61.9 | 55.7 | 68.1 | +4.1 | −2.8 | +11.0 | 237 |
| anes | Born 1911 to 1926 | 1996 | 64.0 | 56.0 | 72.0 | +6.5 | −2.4 | +15.3 | 163 |
| anes | Born 1927 to 1942 | 1956 | 42.1 | 34.9 | 49.4 | +2.2 | −5.7 | +10.0 | 178 |
| anes | Born 1927 to 1942 | 1960 | n/a | n/a | n/a | n/a | n/a | n/a | n/a |
| anes | Born 1927 to 1942 | 1964 | 70.5 | 65.6 | 75.3 | +4.3 | −1.6 | +10.2 | 342 |
| anes | Born 1927 to 1942 | 1968 | 50.4 | 44.5 | 56.2 | +6.0 | −1.0 | +13.0 | 284 |
| anes | Born 1927 to 1942 | 1972 | 34.8 | 30.3 | 39.2 | −1.4 | −6.6 | +3.8 | 446 |
| anes | Born 1927 to 1942 | 1976 | 47.2 | 41.9 | 52.6 | −5.3 | −11.5 | +1.0 | 351 |
| anes | Born 1927 to 1942 | 1980 | 38.4 | 32.0 | 44.8 | −7.2 | −14.7 | +0.2 | 224 |
| anes | Born 1927 to 1942 | 1984 | 40.4 | 35.0 | 45.8 | −1.8 | −8.0 | +4.4 | 319 |
| anes | Born 1927 to 1942 | 1988 | 48.9 | 43.0 | 54.8 | +2.3 | −4.4 | +9.1 | 276 |
| anes | Born 1927 to 1942 | 1992 | 56.0 | 50.3 | 61.8 | −3.2 | −9.6 | +3.3 | 289 |
| anes | Born 1927 to 1942 | 1996 | 55.9 | 49.0 | 62.9 | −3.1 | −11.0 | +4.8 | 230 |
| anes | Born 1927 to 1942 | 2000 | 48.4 | 41.2 | 55.6 | −4.7 | −12.8 | +3.4 | 226 |
| anes | Born 1927 to 1942 | 2004 | 50.5 | 42.3 | 58.8 | +0.9 | −8.4 | +10.1 | 170 |
| anes | Born 1927 to 1942 | 2008 | 41.2 | 33.1 | 49.2 | −16.4 | −25.1 | −7.7 | 224 |
| anes | Born 1927 to 1942 | 2012 | 43.8 | 38.1 | 49.4 | −11.2 | −17.3 | −5.2 | 520 |
| anes | Born 1927 to 1942 | 2016 | 40.9 | 33.4 | 48.3 | −13.3 | −21.1 | −5.4 | 256 |
| anes | Born 1927 to 1942 | 2020 | 47.5 | 40.9 | 54.2 | −9.2 | −16.1 | −2.3 | 415 |
| anes | Born 1927 to 1942 | 2024 | 59.0 | 49.3 | 68.6 | +4.6 | −5.3 | +14.6 | 204 |
| anes | Born 1943 to 1958 | 1972 | 47.4 | 42.5 | 52.3 | +15.6 | +10.1 | +21.2 | 403 |
| anes | Born 1943 to 1958 | 1976 | 53.0 | 47.8 | 58.1 | +2.7 | −3.4 | +8.8 | 378 |
| anes | Born 1943 to 1958 | 1980 | 41.3 | 35.5 | 47.1 | −3.6 | −10.7 | +3.5 | 276 |
| anes | Born 1943 to 1958 | 1984 | 41.0 | 36.8 | 45.2 | −1.3 | −6.7 | +4.1 | 529 |
| anes | Born 1943 to 1958 | 1988 | 47.0 | 42.4 | 51.6 | −0.2 | −6.0 | +5.7 | 449 |
| anes | Born 1943 to 1958 | 1992 | 58.5 | 53.9 | 63.0 | −0.1 | −5.6 | +5.5 | 453 |
| anes | Born 1943 to 1958 | 1996 | 58.0 | 52.2 | 63.9 | −0.5 | −7.7 | +6.6 | 336 |
| anes | Born 1943 to 1958 | 2000 | 53.3 | 47.8 | 58.8 | +1.6 | −5.3 | +8.4 | 380 |
| anes | Born 1943 to 1958 | 2004 | 44.0 | 37.3 | 50.7 | −8.3 | −16.4 | −0.2 | 259 |
| anes | Born 1943 to 1958 | 2008 | 53.5 | 47.8 | 59.3 | −2.2 | −9.0 | +4.7 | 451 |
| anes | Born 1943 to 1958 | 2012 | 50.6 | 47.2 | 54.1 | −4.3 | −8.5 | 0.0 | 1,481 |
| anes | Born 1943 to 1958 | 2016 | 48.1 | 44.0 | 52.2 | −6.8 | −11.8 | −1.8 | 802 |
| anes | Born 1943 to 1958 | 2020 | 53.9 | 50.7 | 57.1 | −3.1 | −6.9 | +0.8 | 1,835 |
| anes | Born 1943 to 1958 | 2024 | 56.7 | 52.7 | 60.7 | +2.7 | −2.1 | +7.5 | 1,155 |
| anes | Born 1959 to 1974 | 1984 | 42.4 | 34.5 | 50.3 | +0.6 | −7.7 | +9.0 | 151 |
| anes | Born 1959 to 1974 | 1988 | 48.3 | 40.9 | 55.7 | +1.4 | −6.6 | +9.4 | 176 |
| anes | Born 1959 to 1974 | 1992 | 58.5 | 53.1 | 63.8 | −0.1 | −6.2 | +6.1 | 330 |
| anes | Born 1959 to 1974 | 1996 | 57.6 | 51.0 | 64.2 | −1.1 | −8.8 | +6.6 | 263 |
| anes | Born 1959 to 1974 | 2000 | 46.5 | 40.6 | 52.4 | −8.2 | −15.2 | −1.1 | 328 |
| anes | Born 1959 to 1974 | 2004 | 45.2 | 38.0 | 52.4 | −6.5 | −14.9 | +2.0 | 211 |
| anes | Born 1959 to 1974 | 2008 | 55.7 | 50.0 | 61.3 | +0.8 | −6.0 | +7.6 | 462 |
| anes | Born 1959 to 1974 | 2012 | 53.9 | 50.1 | 57.7 | +0.4 | −4.1 | +4.9 | 1,171 |
| anes | Born 1959 to 1974 | 2016 | 49.8 | 45.3 | 54.2 | −4.4 | −9.7 | +0.8 | 664 |
| anes | Born 1959 to 1974 | 2020 | 50.2 | 46.9 | 53.6 | −8.5 | −12.4 | −4.5 | 1,561 |
| anes | Born 1959 to 1974 | 2024 | 50.6 | 46.4 | 54.8 | −5.5 | −10.5 | −0.5 | 1,061 |
| anes | Born 1975 to 1990 | 2004 | 66.0 | 57.3 | 74.7 | +19.7 | +10.1 | +29.3 | 137 |
| anes | Born 1975 to 1990 | 2008 | 64.9 | 58.5 | 71.4 | +13.1 | +5.7 | +20.4 | 337 |
| anes | Born 1975 to 1990 | 2012 | 60.0 | 55.5 | 64.6 | +8.5 | +3.4 | +13.5 | 827 |
| anes | Born 1975 to 1990 | 2016 | 62.8 | 58.2 | 67.4 | +12.7 | +7.4 | +18.1 | 604 |
| anes | Born 1975 to 1990 | 2020 | 58.4 | 55.1 | 61.8 | +2.9 | −1.0 | +6.9 | 1,454 |
| anes | Born 1975 to 1990 | 2024 | 55.6 | 51.3 | 60.0 | +1.5 | −3.7 | +6.6 | 964 |
| anes | Born 1991 or later | 2016 | 62.9 | 54.2 | 71.6 | +11.2 | +2.1 | +20.2 | 177 |
| anes | Born 1991 or later | 2020 | 69.6 | 64.3 | 74.9 | +15.9 | +10.4 | +21.5 | 573 |
| anes | Born 1991 or later | 2024 | 55.1 | 49.0 | 61.1 | +0.7 | −5.9 | +7.2 | 452 |
| ces | Born 1927 to 1942 | 2008 | 42.2 | 40.3 | 44.0 | −13.8 | −15.8 | −11.7 | 3,830 |
| ces | Born 1927 to 1942 | 2012 | 40.7 | 38.9 | 42.5 | −13.8 | −15.8 | −11.8 | 5,912 |
| ces | Born 1927 to 1942 | 2016 | 38.0 | 35.6 | 40.5 | −14.1 | −16.7 | −11.6 | 3,561 |
| ces | Born 1927 to 1942 | 2020 | 36.8 | 34.2 | 39.4 | −16.6 | −19.3 | −14.0 | 2,320 |
| ces | Born 1927 to 1942 | 2024 | 35.4 | 31.8 | 39.0 | −13.9 | −17.5 | −10.2 | 1,150 |
| ces | Born 1943 to 1958 | 2008 | 50.8 | 49.5 | 52.1 | −4.3 | −5.9 | −2.7 | 7,691 |
| ces | Born 1943 to 1958 | 2012 | 49.2 | 48.2 | 50.2 | −5.9 | −7.3 | −4.4 | 17,779 |
| ces | Born 1943 to 1958 | 2016 | 46.4 | 45.2 | 47.5 | −6.9 | −8.3 | −5.5 | 13,874 |
| ces | Born 1943 to 1958 | 2020 | 48.1 | 46.9 | 49.3 | −6.4 | −7.8 | −5.0 | 12,855 |
| ces | Born 1943 to 1958 | 2024 | 46.3 | 45.1 | 47.6 | −3.5 | −5.1 | −2.0 | 12,790 |
| ces | Born 1959 to 1974 | 2008 | 52.7 | 51.4 | 54.1 | −1.7 | −3.3 | 0.0 | 7,281 |
| ces | Born 1959 to 1974 | 2012 | 53.4 | 51.9 | 54.8 | +0.4 | −1.3 | +2.1 | 8,300 |
| ces | Born 1959 to 1974 | 2016 | 48.2 | 47.0 | 49.3 | −3.9 | −5.3 | −2.5 | 12,150 |
| ces | Born 1959 to 1974 | 2020 | 48.9 | 47.8 | 49.9 | −5.3 | −6.6 | −4.0 | 13,938 |
| ces | Born 1959 to 1974 | 2024 | 42.9 | 41.7 | 44.1 | −9.0 | −10.5 | −7.5 | 15,336 |
| ces | Born 1975 to 1990 | 2008 | 66.3 | 64.6 | 68.0 | +16.6 | +14.7 | +18.5 | 4,555 |
| ces | Born 1975 to 1990 | 2012 | 62.5 | 60.6 | 64.4 | +12.4 | +10.3 | +14.4 | 4,875 |
| ces | Born 1975 to 1990 | 2016 | 60.3 | 59.0 | 61.6 | +12.2 | +10.7 | +13.7 | 9,329 |
| ces | Born 1975 to 1990 | 2020 | 61.3 | 60.1 | 62.5 | +11.3 | +9.9 | +12.7 | 10,393 |
| ces | Born 1975 to 1990 | 2024 | 54.6 | 53.0 | 56.2 | +7.5 | +5.7 | +9.3 | 8,460 |
| ces | Born 1991 or later | 2012 | 58.8 | 53.8 | 63.9 | +6.0 | +0.9 | +11.2 | 758 |
| ces | Born 1991 or later | 2016 | 67.7 | 65.0 | 70.4 | +18.0 | +15.2 | +20.8 | 1,925 |
| ces | Born 1991 or later | 2020 | 67.8 | 65.9 | 69.7 | +16.9 | +14.8 | +18.9 | 4,360 |
| ces | Born 1991 or later | 2024 | 59.0 | 56.5 | 61.6 | +11.9 | +9.3 | +14.6 | 4,272 |

Views: ANES, lead over other voters (panel = anes); ANES, Democratic share (panel = anes); CES, lead over other voters (panel = ces); CES, Democratic share (panel = ces).

Note: Cohorts are the 16-year birth groups of the ANES cumulative file, and the CES uses the same groups from reported birth year. Cohort cells include every voter with a known cohort, whether or not the age is known. A cell is plotted only when it has 100 or more respondents and a Kish effective sample size (the sample size after weighting) of 100 or more, the floor of this chapter. A blank cell leaves a gap in the line.

Note: The comparison group is every other voter in the same election with a known cohort, so the cohort and the comparison group are different respondents. The measure removes anything that moves all voters together in an election, and it does not remove the effect of age or the changing make-up of the comparison group. The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel.

Source: ANES Cumulative Data File, presidential elections 1952-2024; weighted (post-election weight where the file has one, otherwise VCF0009z); two-party presidential voters; CES view: CES Cumulative File, presidential elections 2008-2024; weighted (weight_cumulative); two-party presidential voters

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/cohort_lines.json

### Table 6. The vote lead of the 1975 to 1990 cohort over other voters changed by −18.2 points in the ANES between 2004 and 2024 and by −9.1 in the CES between 2008 and 2024

Democratic share of a cohort's two-party voters minus the share among voters born in other years, first and last cell with enough voters; ANES presidential elections 1952 to 2024; 95% intervals; the buttons switch survey and measure

| Measure | Birth cohort and cells | Lead in first cell (points) | 95% interval low (first) | 95% interval high (first) | Lead in last cell (points) | 95% interval low (last) | 95% interval high (last) | Change (points) | Respondents, first cell | Respondents, last cell |
| --- | --- | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: |
| anes_vote | Born 1895 to 1910 (1952 to 1980) | −4.6 | −10.7 | +1.4 | +7.1 | −3.3 | +17.4 | +11.7 | 373 | 102 |
| anes_vote | Born 1911 to 1926 (1952 to 1996) | +7.8 | +2.0 | +13.6 | +6.5 | −2.4 | +15.3 | −1.4 | 453 | 163 |
| anes_vote | Born 1927 to 1942 (1956 to 2024) | +2.2 | −5.7 | +10.0 | +4.6 | −5.3 | +14.6 | +2.5 | 178 | 204 |
| anes_vote | Born 1943 to 1958 (1972 to 2024) | +15.6 | +10.1 | +21.2 | +2.7 | −2.1 | +7.5 | −12.9 | 403 | 1,155 |
| anes_vote | Born 1959 to 1974 (1984 to 2024) | +0.6 | −7.7 | +9.0 | −5.5 | −10.5 | −0.5 | −6.1 | 151 | 1,061 |
| anes_vote | Born 1975 to 1990 (2004 to 2024) | +19.7 | +10.1 | +29.3 | +1.5 | −3.7 | +6.6 | −18.2 | 137 | 964 |
| anes_vote | Born 1991 or later (2016 to 2024) | +11.2 | +2.1 | +20.2 | +0.7 | −5.9 | +7.2 | −10.5 | 177 | 452 |
| ces_vote | Born 1927 to 1942 (2008 to 2024) | −13.8 | −15.8 | −11.7 | −13.9 | −17.5 | −10.2 | −0.1 | 3,830 | 1,150 |
| ces_vote | Born 1943 to 1958 (2008 to 2024) | −4.3 | −5.9 | −2.7 | −3.5 | −5.1 | −2.0 | +0.8 | 7,691 | 12,790 |
| ces_vote | Born 1959 to 1974 (2008 to 2024) | −1.7 | −3.3 | 0.0 | −9.0 | −10.5 | −7.5 | −7.3 | 7,281 | 15,336 |
| ces_vote | Born 1975 to 1990 (2008 to 2024) | +16.6 | +14.7 | +18.5 | +7.5 | +5.7 | +9.3 | −9.1 | 4,555 | 8,460 |
| ces_vote | Born 1991 or later (2012 to 2024) | +6.0 | +0.9 | +11.2 | +11.9 | +9.3 | +14.6 | +5.9 | 758 | 4,272 |
| anes_pid | Born 1895 to 1910 (1952 to 1988) | −1.7 | −6.9 | +3.5 | −0.5 | −10.6 | +9.6 | +1.2 | 484 | 100 |
| anes_pid | Born 1911 to 1926 (1952 to 2000) | +6.7 | +1.8 | +11.5 | +11.2 | +2.2 | +20.3 | +4.6 | 625 | 141 |
| anes_pid | Born 1927 to 1942 (1952 to 2024) | +5.9 | −2.4 | +14.2 | +4.6 | −4.7 | +13.9 | −1.3 | 134 | 240 |
| anes_pid | Born 1943 to 1958 (1968 to 2024) | +4.6 | −4.2 | +13.4 | +1.2 | −3.3 | +5.7 | −3.4 | 121 | 1,339 |
| anes_pid | Born 1959 to 1974 (1984 to 2024) | −0.2 | −6.5 | +6.1 | −5.9 | −10.4 | −1.4 | −5.7 | 285 | 1,324 |
| anes_pid | Born 1975 to 1990 (2000 to 2024) | +8.6 | −0.8 | +18.0 | −0.3 | −4.8 | +4.3 | −8.8 | 135 | 1,301 |
| anes_pid | Born 1991 or later (2012 to 2024) | +10.2 | +0.7 | +19.6 | +4.2 | −1.0 | +9.4 | −6.0 | 189 | 765 |
| ces_pid | Born 1927 to 1942 (2006 to 2024) | −6.2 | −7.7 | −4.7 | −15.8 | −19.5 | −12.0 | −9.6 | 5,626 | 1,178 |
| ces_pid | Born 1943 to 1958 (2006 to 2024) | −3.4 | −4.7 | −2.1 | −5.2 | −6.7 | −3.6 | −1.7 | 11,395 | 13,339 |
| ces_pid | Born 1959 to 1974 (2006 to 2024) | −2.6 | −3.9 | −1.3 | −9.8 | −11.3 | −8.2 | −7.2 | 9,611 | 16,895 |
| ces_pid | Born 1975 to 1990 (2006 to 2024) | +12.1 | +10.5 | +13.7 | +7.3 | +5.5 | +9.0 | −4.8 | 4,631 | 10,549 |
| ces_pid | Born 1991 or later (2010 to 2024) | +18.7 | +12.4 | +25.0 | +11.4 | +9.2 | +13.6 | −7.3 | 302 | 8,886 |

Views: ANES vote (panel = anes_vote); CES vote (panel = ces_vote); ANES party identification (panel = anes_pid); CES party identification (panel = ces_pid).

Note: A cohort's first cell holds only the members old enough to vote at that election, and the first cell of an older cohort is often long after it entered the electorate. The row label gives the years of the two cells.

Note: The two ends of a row are different respondents, and the interval of the change combines their standard errors. Intervals are model based: they treat the weighted sample as a simple random sample and ignore clustering and stratification.

Source: ANES Cumulative Data File, presidential elections 1952-2024; weighted (post-election weight where the file has one, otherwise VCF0009z); two-party presidential voters; other views: CES and party identification as named on the buttons

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/cohort_first_last.json

### Table 7. In 2020 and 2024 the age gap in the vote was +20.2 points among white voters and −12.3 among Black voters

Democratic share of two-party voters aged 18 to 29 minus the share among voters aged 65 and over, by gender and race, CES 2008 and 2012 pooled and 2020 and 2024 pooled; 95% intervals

| Voters | Gap 2008 and 2012 (points) | 95% interval low | 95% interval high | Respondents, early | Gap 2020 and 2024 (points) | 95% interval low (late) | 95% interval high (late) | Respondents, late | Change (points) |
| --- | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: |
| All voters | +21.6 | +19.7 | +23.5 | 22,508 | +18.1 | +16.0 | +20.2 | 34,342 | −3.5 |
| Women | +17.3 | +14.9 | +19.7 | 11,936 | +16.1 | +13.4 | +18.7 | 18,877 | −1.3 |
| Men | +27.0 | +24.1 | +29.8 | 10,572 | +19.9 | +16.6 | +23.1 | 15,342 | −7.1 |
| White | +18.0 | +15.9 | +20.2 | 19,158 | +20.2 | +17.7 | +22.7 | 26,464 | +2.1 |
| Black | +0.6 | −2.8 | +4.0 | 1,153 | −12.3 | −17.7 | −6.8 | 3,055 | −12.9 |
| Hispanic | +22.1 | +12.9 | +31.2 | 1,208 | +5.3 | −1.7 | +12.3 | 2,555 | −16.8 |

Note: Pooling two elections gives every cell the floor of 100 respondents and an effective sample of 100. Asian voters fall below it in the earlier period and are left out. In 2020 and 2024 pooled their gap is +12.9.

Note: Race is the CES single-race category with Hispanic voters of any race as a separate group, and the groups overlap with the gender rows. The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel. Intervals are model based: they treat the weighted sample as a simple random sample and ignore clustering and stratification.

Source: CES Cumulative File, presidential elections 2008-2024; weighted (weight_cumulative); two-party presidential voters; elections pooled in two groups

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/age_gap_groups.json

### Table 8. In the CES the vote moved by −4.3 points per decade of age within an election, −1.2 per decade at a fixed age and −5.2 along a cohort

Change in the Democratic share of the two-party vote per decade, three straight-line comparisons, voters aged 18 to 73, ANES 1952 to 2024 and CES 2008 to 2024; 95% intervals (HC3)

| Comparison | Survey | Change (points per decade) | 95% interval low | 95% interval high | Voters aged 18 to 73 |
| --- | --- | ---: | ---: | ---: | ---: |
| One decade older, same election (age and birth year) | ANES 1952 to 2024 | −2.2 | −2.6 | −1.7 | 30,571 |
| One decade older, same election (age and birth year) | CES 2008 to 2024 | −4.3 | −4.6 | −4.1 | 169,858 |
| One decade later, same age (election and birth year) | ANES 1952 to 2024 | +1.6 | +1.3 | +1.9 | 30,571 |
| One decade later, same age (election and birth year) | CES 2008 to 2024 | −1.2 | −1.8 | −0.5 | 169,858 |
| One decade later, same birth cohort (age and election) | ANES 1952 to 2024 | +0.3 | −0.3 | +0.8 | 30,571 |
| One decade later, same birth cohort (age and election) | CES 2008 to 2024 | −5.2 | −5.9 | −4.6 | 169,858 |

Note: Cross-section: weighted regression of the 0/1 Democratic vote on age in decades with a fixed effect for each election. Same age: regression on election year in decades with a fixed effect for each 4-year age band. Same cohort: regression on election year in decades with a fixed effect for each 4-year birth band. Voters aged 18 to 73 only, so the age and birth bands share one grid.

Note: The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel.

Source: ANES Cumulative Data File, presidential elections 1952-2024; weighted (post-election weight where the file has one, otherwise VCF0009z); two-party presidential voters; CES Cumulative File, presidential elections 2008-2024; weighted (weight_cumulative); two-party presidential voters; weighted regression coefficients

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/three_comparisons.json

### Table 9. In the CES the age effect from the youngest to the oldest band is −22.2 points if birth years carry no trend, −27.3 if elections carry none and +1.0 if ages carry none

Age effect on the Democratic share of the two-party vote, points, 4-year age bands from 18 to 73, from a model with an effect for every age band, election and birth cohort, under three constraints; 95% bootstrap intervals

| Survey | Constraint | Age band midpoint (years) | Age effect (points) | 95% bootstrap interval low | 95% bootstrap interval high |
| --- | --- | ---: | ---: | ---: | ---: |
| ces | No trend across birth years | 19.5 | +11.9 | +9.5 | +14.2 |
| ces | No trend across birth years | 23.5 | +11.5 | +9.5 | +13.4 |
| ces | No trend across birth years | 27.5 | +8.1 | +6.3 | +9.8 |
| ces | No trend across birth years | 31.5 | +6.8 | +5.1 | +8.5 |
| ces | No trend across birth years | 35.5 | +3.9 | +2.3 | +5.6 |
| ces | No trend across birth years | 39.5 | +2.1 | +0.6 | +3.5 |
| ces | No trend across birth years | 43.5 | +0.8 | −0.6 | +2.2 |
| ces | No trend across birth years | 47.5 | −1.5 | −2.8 | −0.2 |
| ces | No trend across birth years | 51.5 | −4.6 | −5.8 | −3.3 |
| ces | No trend across birth years | 55.5 | −6.0 | −7.2 | −4.7 |
| ces | No trend across birth years | 59.5 | −7.0 | −8.3 | −5.8 |
| ces | No trend across birth years | 63.5 | −7.7 | −9.0 | −6.4 |
| ces | No trend across birth years | 67.5 | −8.0 | −9.7 | −6.6 |
| ces | No trend across birth years | 71.5 | −10.3 | −11.8 | −8.6 |
| ces | No trend across elections | 19.5 | +14.5 | +11.6 | +17.3 |
| ces | No trend across elections | 23.5 | +13.6 | +11.5 | +15.8 |
| ces | No trend across elections | 27.5 | +9.8 | +7.9 | +11.8 |
| ces | No trend across elections | 31.5 | +8.1 | +6.4 | +10.0 |
| ces | No trend across elections | 35.5 | +4.9 | +3.3 | +6.6 |
| ces | No trend across elections | 39.5 | +2.7 | +1.1 | +4.1 |
| ces | No trend across elections | 43.5 | +1.0 | −0.4 | +2.3 |
| ces | No trend across elections | 47.5 | −1.7 | −3.0 | −0.4 |
| ces | No trend across elections | 51.5 | −5.2 | −6.6 | −3.8 |
| ces | No trend across elections | 55.5 | −7.0 | −8.3 | −5.6 |
| ces | No trend across elections | 59.5 | −8.4 | −9.7 | −7.0 |
| ces | No trend across elections | 63.5 | −9.4 | −10.9 | −8.0 |
| ces | No trend across elections | 67.5 | −10.2 | −12.1 | −8.6 |
| ces | No trend across elections | 71.5 | −12.8 | −14.7 | −10.8 |
| ces | No trend across ages | 19.5 | +0.3 | −1.6 | +2.2 |
| ces | No trend across ages | 23.5 | +1.6 | 0.0 | +3.2 |
| ces | No trend across ages | 27.5 | 0.0 | −1.4 | +1.4 |
| ces | No trend across ages | 31.5 | +0.5 | −0.9 | +2.0 |
| ces | No trend across ages | 35.5 | −0.6 | −2.0 | +0.9 |
| ces | No trend across ages | 39.5 | −0.6 | −2.0 | +0.8 |
| ces | No trend across ages | 43.5 | −0.1 | −1.5 | +1.3 |
| ces | No trend across ages | 47.5 | −0.6 | −1.9 | +0.7 |
| ces | No trend across ages | 51.5 | −1.9 | −3.1 | −0.7 |
| ces | No trend across ages | 55.5 | −1.5 | −2.5 | −0.4 |
| ces | No trend across ages | 59.5 | −0.8 | −1.8 | +0.2 |
| ces | No trend across ages | 63.5 | +0.4 | −0.5 | +1.3 |
| ces | No trend across ages | 67.5 | +1.8 | +0.6 | +2.8 |
| ces | No trend across ages | 71.5 | +1.3 | +0.1 | +2.7 |
| anes | No trend across birth years | 19.5 | +10.4 | +6.8 | +14.2 |
| anes | No trend across birth years | 23.5 | +4.2 | +1.4 | +7.2 |
| anes | No trend across birth years | 27.5 | +3.1 | +0.5 | +5.9 |
| anes | No trend across birth years | 31.5 | +0.8 | −1.6 | +3.2 |
| anes | No trend across birth years | 35.5 | +0.1 | −2.1 | +2.4 |
| anes | No trend across birth years | 39.5 | −2.8 | −5.0 | −0.7 |
| anes | No trend across birth years | 43.5 | −1.1 | −3.4 | +1.2 |
| anes | No trend across birth years | 47.5 | −0.2 | −2.6 | +2.2 |
| anes | No trend across birth years | 51.5 | −0.7 | −3.2 | +1.5 |
| anes | No trend across birth years | 55.5 | −3.3 | −5.7 | −1.1 |
| anes | No trend across birth years | 59.5 | −2.5 | −5.0 | −0.2 |
| anes | No trend across birth years | 63.5 | −3.3 | −5.7 | −0.9 |
| anes | No trend across birth years | 67.5 | −1.9 | −4.6 | +0.6 |
| anes | No trend across birth years | 71.5 | −2.9 | −5.6 | −0.1 |
| anes | No trend across elections | 19.5 | +6.2 | +2.4 | +10.3 |
| anes | No trend across elections | 23.5 | +0.6 | −2.2 | +3.6 |
| anes | No trend across elections | 27.5 | +0.2 | −2.3 | +2.9 |
| anes | No trend across elections | 31.5 | −1.5 | −3.9 | +1.0 |
| anes | No trend across elections | 35.5 | −1.5 | −3.7 | +0.7 |
| anes | No trend across elections | 39.5 | −3.8 | −5.9 | −1.6 |
| anes | No trend across elections | 43.5 | −1.4 | −3.7 | +0.9 |
| anes | No trend across elections | 47.5 | +0.2 | −2.3 | +2.6 |
| anes | No trend across elections | 51.5 | +0.3 | −2.2 | +2.5 |
| anes | No trend across elections | 55.5 | −1.7 | −4.1 | +0.6 |
| anes | No trend across elections | 59.5 | −0.2 | −2.5 | +2.0 |
| anes | No trend across elections | 63.5 | −0.4 | −2.7 | +2.1 |
| anes | No trend across elections | 67.5 | +1.6 | −1.1 | +4.2 |
| anes | No trend across elections | 71.5 | +1.3 | −1.6 | +4.1 |
| anes | No trend across ages | 19.5 | +5.7 | +2.5 | +9.0 |
| anes | No trend across ages | 23.5 | +0.2 | −2.3 | +2.8 |
| anes | No trend across ages | 27.5 | −0.2 | −2.5 | +2.5 |
| anes | No trend across ages | 31.5 | −1.8 | −4.2 | +0.6 |
| anes | No trend across ages | 35.5 | −1.7 | −3.8 | +0.5 |
| anes | No trend across ages | 39.5 | −3.9 | −6.1 | −1.7 |
| anes | No trend across ages | 43.5 | −1.4 | −3.7 | +0.8 |
| anes | No trend across ages | 47.5 | +0.2 | −2.2 | +2.6 |
| anes | No trend across ages | 51.5 | +0.4 | −2.0 | +2.5 |
| anes | No trend across ages | 55.5 | −1.5 | −3.7 | +0.7 |
| anes | No trend across ages | 59.5 | 0.0 | −2.2 | +2.3 |
| anes | No trend across ages | 63.5 | 0.0 | −2.4 | +2.3 |
| anes | No trend across ages | 67.5 | +2.1 | −0.2 | +4.4 |
| anes | No trend across ages | 71.5 | +1.8 | −0.5 | +4.1 |

Views: CES 2008 to 2024 (panel = ces); ANES 1952 to 2024 (panel = anes).

Note: The model gives each 4-year age band from 18 to 73, each presidential election and each 4-year birth cohort an effect on the Democratic share, and is fitted by weighted least squares to the cell means (the linear probability model). Because birth year equals election year minus age, the three sets of effects are not identified: adding a straight line to the age effects and the cohort effects and subtracting one from the election effects leaves every fitted cell unchanged. The profile shown is the minimum-norm fit shifted by the straight line that gives the stated constraint.

Note: The fitted shares in every cell are identical under the three constraints, to within floating-point rounding. Voters aged 74 and over fall outside the 4-year grid. The CES is an opt-in online panel, so its intervals describe sampling variation among panel members and leave out how respondents joined the panel.

Source: CES Cumulative File, presidential elections 2008-2024; weighted (weight_cumulative); two-party presidential voters; weighted least squares on the age-by-election grid, seeded respondent bootstrap

Data: https://vishalsingh.org/politics/report/age-and-generation/figures/apc_profiles.json

## All estimates

Every fact in facts.json (150), sorted by id.

| Fact id | Value | Unit | Estimand | Population | Period | Interval | n | Weights | Source | Note |
| --- | ---: | --- | --- | --- | --- | --- | ---: | --- | --- | --- |
| anes_chg_2024 | −18.2 | percentage points of Democratic two-party vote share | age gap in 2024 minus age gap in 2020; different respondents, standard errors combined | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −28.4 to −7.9 | 4,146 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_ftf_gap_2012 | +21.7 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2012, face-to-face interviews | 95% CI 9.2 to 34.3 | 446 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_gap_1992 | +2.9 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 1992 | 95% CI −5.9 to 11.8 | 488 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_gap_2008 | +22.6 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008 | 95% CI 12.2 to 33.0 | 516 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_gap_2020 | +17.0 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 | 95% CI 11.0 to 23.1 | 2,471 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_gap_2024 | −1.1 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2024 | 95% CI −9.4 to 7.1 | 1,675 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_lean_2020 | +3.5 | percentage points of Democratic two-party vote share | ANES Democratic share minus the certified Democratic share of the two-party vote | two-party presidential voters | 2020 | 95% CI 1.7 to 5.2 | 6,076 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_lean_2024 | +5.3 | percentage points of Democratic two-party vote share | ANES Democratic share minus the certified Democratic share of the two-party vote | two-party presidential voters | 2024 | 95% CI 3.0 to 7.5 | 3,933 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_minus_ces_mid_2024 | +7.8 | percentage points of Democratic two-party vote share | ANES Democratic share minus CES Democratic share in the same age group; independent surveys | two-party presidential voters aged 45 to 64 | 2024 | 95% CI 3.8 to 11.9 | 18,084 | weight_postelection where the file has one, otherwise weight (VCF0009z) and weight_cumulative | ANES Cumulative Data File |   |
| anes_minus_ces_old_2024 | +11.9 | percentage points of Democratic two-party vote share | ANES Democratic share minus CES Democratic share in the same age group; independent surveys | two-party presidential voters aged 65 and over | 2024 | 95% CI 8.0 to 15.7 | 16,395 | weight_postelection where the file has one, otherwise weight (VCF0009z) and weight_cumulative | ANES Cumulative Data File |   |
| anes_minus_ces_young_2024 | −4.3 | percentage points of Democratic two-party vote share | ANES Democratic share minus CES Democratic share in the same age group; independent surveys | two-party presidential voters aged 18 to 29 | 2024 | 95% CI −12.3 to 3.6 | 3,367 | weight_postelection where the file has one, otherwise weight (VCF0009z) and weight_cumulative | ANES Cumulative Data File |   |
| anes_neff_ftf_2024 | 31 | respondents | Kish effective sample size | two-party presidential voters aged 18 to 29, face-to-face interviews | 2024 |   | 64 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_neff_web_2024 | 86 | respondents | Kish effective sample size | two-party presidential voters aged 18 to 29, web interviews | 2024 |   | 156 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_nomode_2024 | 1,884 | respondents | count of respondents | two-party presidential voters with no interview-mode weight (panel and paper cases) | 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| anes_nomode_share_2024 | 48% | share of respondents | share with no interview-mode weight, unweighted count | two-party presidential voters with a positive vote weight | 2024 |   | 3,933 | none (count) | ANES Cumulative Data File |   |
| anes_old_2008 | 44.9% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 65 and over | 2008 | 95% CI 37.9% to 52.0% | 294 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_old_2024 | 57.4% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 65 and over | 2024 | 95% CI 53.7% to 61.1% | 1,390 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_pid_chg | −12.6 | percentage points of the Democratic share of party identifiers | age gap in 2024 minus age gap in 2020; different respondents | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −21.1 to −4.0 | 4,993 | weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_pid_gap_2020 | +14.5 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2020 | 95% CI 9.2 to 19.8 | 2,883 | weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_pid_gap_2024 | +1.9 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2024 | 95% CI −4.7 to 8.6 | 2,110 | weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_pid_web_gap_2024 | +1.1 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2024, web interviews | 95% CI −8.9 to 11.2 | 734 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_share_2024 | 54.5% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters (age may be missing) | 2024 | 95% CI 52.3% to 56.7% | 3,933 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_web_gap_2012 | +12.8 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2012, web interviews | 95% CI 4.2 to 21.5 | 1,038 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_web_gap_2016 | +19.3 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2016, web interviews | 95% CI 10.0 to 28.7 | 683 | weight_ftf (face-to-face) and weight_web (web) | ANES Cumulative Data File |   |
| anes_young_2008 | 67.5% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 18 to 29 | 2008 | 95% CI 59.8% to 75.2% | 222 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| anes_young_2024 | 56.3% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 18 to 29 | 2024 | 95% CI 48.9% to 63.6% | 285 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| apc_anes_span_age | −3.8 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in age; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 1952 to 2024 | 95% CI −7.8 to −0.2 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| apc_anes_span_cohort | −13.3 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in cohort; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 1952 to 2024 | 95% CI −18.5 to −8.7 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| apc_anes_span_period | −4.8 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in period; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 1952 to 2024 | 95% CI −10.3 to 0.0 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| apc_bands | 14 | age bands | count of age bands in the grid model | 4-year age bands from 18 to 73 | all |   |   | none (count) | ANES Cumulative Data File |   |
| apc_ces_span_age | +1.0 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in age; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 2008 to 2024 | 95% CI −0.8 to 3.1 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| apc_ces_span_cohort | −22.2 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in cohort; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 2008 to 2024 | 95% CI −25.0 to −19.2 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| apc_ces_span_period | −27.3 | percentage points of Democratic two-party vote share | oldest age band's effect minus youngest age band's effect under the constraint of no straight-line trend in period; seeded percentile bootstrap | two-party presidential voters aged 18 to 73, 4-year age bands | elections 2008 to 2024 | 95% CI −31.5 to −23.3 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| apc_reps | 1,000 | replicates | count of bootstrap replicates | bootstrap replicates | all |   |   | none (count) | ANES Cumulative Data File |   |
| cert_share_2024 | 49.2% | percent of the two-party presidential vote | certified Democratic share of the two-party vote | ballots counted for the two major-party candidates | 2024 |   |   | none (full counts) | State presidential returns |   |
| ces_45_65_2024 | −1.6 | percentage points of Democratic two-party vote share | Democratic share among voters aged 45 to 64 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 45 to 64 and aged 65 and over | 2024 | 95% CI −3.2 to 0.0 | 31,853 | weight_cumulative | Cooperative Election Study |   |
| ces_band_1824_2529_2012 | +0.5 | percentage points of Democratic two-party vote share | Democratic share in the younger band minus the share in the next older band | two-party presidential voters aged 18 to 24 and aged 25 to 29 | 2012 | 95% CI −4.3 to 5.2 | 3,552 | weight_cumulative | Cooperative Election Study |   |
| ces_band_2529_3044_2012 | +2.9 | percentage points of Democratic two-party vote share | Democratic share in the younger band minus the share in the next older band | two-party presidential voters aged 25 to 29 and aged 30 to 44 | 2012 | 95% CI −0.9 to 6.7 | 6,289 | weight_cumulative | Cooperative Election Study |   |
| ces_chg_2024 | −7.1 | percentage points of Democratic two-party vote share | age gap in 2024 minus age gap in 2020; different respondents, standard errors combined | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −11.1 to −3.2 | 34,342 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_2008 | +24.5 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008 | 95% CI 21.8 to 27.1 | 7,804 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_2012 | +18.7 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2012 | 95% CI 16.0 to 21.4 | 14,704 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_2016 | +22.9 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2016 | 95% CI 20.4 to 25.3 | 13,890 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_2020 | +22.2 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 | 95% CI 19.9 to 24.4 | 16,255 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_2024 | +15.0 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2024 | 95% CI 11.8 to 18.3 | 18,087 | weight_cumulative | Cooperative Election Study |   |
| ces_gap_max_0820 | +24.5 | percentage points of Democratic two-party vote share | highest age gap among the four elections | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008, 2012, 2016 and 2020 (highest) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_gap_min_0820 | +18.7 | percentage points of Democratic two-party vote share | lowest age gap among the four elections | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008, 2012, 2016 and 2020 (lowest) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_lean_2024 | −0.3 | percentage points of Democratic two-party vote share | CES Democratic share minus the certified Democratic share of the two-party vote | two-party presidential voters | 2024 | 95% CI −1.0 to 0.5 | 42,008 | weight_cumulative | Cooperative Election Study |   |
| ces_matched_gap_2020 | +22.8 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2020 | 95% CI 20.1 to 25.4 | 13,317 | weight_cumulative | Cooperative Election Study |   |
| ces_matched_old_2024 | 46.0% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 65 and over whose registration was matched to voter-file records | 2024 | 95% CI 44.8% to 47.2% | 12,700 | weight_cumulative | Cooperative Election Study |   |
| ces_matched_std_chg | −0.6 | percentage points of Democratic two-party vote share | age gap in 2024 minus age gap in 2020 among matched respondents, standard weight | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −5.6 to 4.5 | 27,420 | weight_cumulative | Cooperative Election Study |   |
| ces_matched_std_gap_2024 | +22.2 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2024 | 95% CI 17.9 to 26.5 | 14,103 | weight_cumulative | Cooperative Election Study |   |
| ces_old_2008 | 42.7% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 65 and over | 2008 | 95% CI 41.0% to 44.5% | 4,477 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_chg | −1.1 | percentage points of the Democratic share of party identifiers | age gap in 2024 minus age gap in 2020; different respondents | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −4.4 to 2.3 | 43,206 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_chg_2018_2024 | −3.3 | percentage points of the Democratic share of party identifiers | age gap at the later wave minus age gap at the earlier wave; different respondents | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2018 to 2024 | 95% CI −6.7 to 0.1 | 43,419 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_chg_2022_2024 | −7.3 | percentage points of the Democratic share of party identifiers | age gap at the later wave minus age gap at the earlier wave; different respondents | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2022 to 2024 | 95% CI −10.6 to −3.9 | 42,990 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_2018 | +17.2 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2018 | 95% CI 15.1 to 19.3 | 20,577 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_2020 | +14.9 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2020 | 95% CI 12.9 to 17.0 | 20,364 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_2022 | +21.1 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2022 | 95% CI 19.0 to 23.3 | 20,148 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_2024 | +13.9 | percentage points of the Democratic share of party identifiers | Democratic share of identifiers aged 18 to 29 minus that of identifiers aged 65 and over | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | 2024 | 95% CI 11.2 to 16.5 | 22,842 | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_max | +21.3 | percentage points of the Democratic share of party identifiers | highest party-identification age gap among ten waves | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | even years 2006 to 2024 (highest) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_pid_gap_min | +13.9 | percentage points of the Democratic share of party identifiers | lowest party-identification age gap among ten waves | party identifiers (leaners included) aged 18 to 29 and aged 65 and over | even years 2006 to 2024 (lowest) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_post_chg_2024 | −5.3 | percentage points of Democratic two-party vote share | age gap in 2024 (weight_cumulative) minus age gap in 2020 (weight_post); the post-election weight does not exist for 2024 | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −9.4 to −1.2 | 34,341 | weight_cumulative and weight_post | Cooperative Election Study |   |
| ces_post_gap_2012 | +19.9 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2012 | 95% CI 17.2 to 22.6 | 14,704 | weight_post (post-election weight) | Cooperative Election Study |   |
| ces_post_gap_2016 | +22.4 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2016 | 95% CI 19.7 to 25.0 | 13,890 | weight_post (post-election weight) | Cooperative Election Study |   |
| ces_post_gap_2020 | +20.4 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 | 95% CI 17.9 to 22.9 | 16,254 | weight_post (post-election weight) | Cooperative Election Study |   |
| ces_share_2024 | 49.0% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters | 2024 | 95% CI 48.2% to 49.7% | 42,008 | weight_cumulative | Cooperative Election Study |   |
| ces_split_max | +5.0 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 24 minus that among voters aged 25 to 29 | two-party presidential voters aged 18 to 24 and aged 25 to 29 | 2008 to 2024 (largest of five elections) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_split_min | +0.5 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 24 minus that among voters aged 25 to 29 | two-party presidential voters aged 18 to 24 and aged 25 to 29 | 2008 to 2024 (smallest of five elections) |   |   | weight_cumulative | Cooperative Election Study |   |
| ces_vv_chg | +0.2 | percentage points of Democratic two-party vote share | age gap in 2024 minus age gap in 2020 among matched respondents, validated-voter weight | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −4.5 to 4.9 | 27,420 | vvweight (validated-voter weight, for respondents whose registration was matched to voter-file records) | Cooperative Election Study |   |
| ces_vv_gap_2024 | +23.0 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2024 | 95% CI 19.1 to 26.9 | 14,103 | vvweight (validated-voter weight, for respondents whose registration was matched to voter-file records) | Cooperative Election Study |   |
| ces_young_2008 | 67.2% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 18 to 29 | 2008 | 95% CI 65.2% to 69.2% | 3,327 | weight_cumulative | Cooperative Election Study |   |
| diff_in_changes_std | −6.6 | percentage points of Democratic two-party vote share | change in the age gap among all voters minus the change among matched respondents (standard weight); seeded percentile bootstrap resampling respondents within each year | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −10.2 to −2.8 | 34,342 | weight_cumulative | Cooperative Election Study |   |
| diff_in_changes_vv | −7.3 | percentage points of Democratic two-party vote share | change in the age gap among all voters minus the change among matched respondents (validated-voter weight); seeded percentile bootstrap resampling respondents within each year | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 to 2024 | 95% CI −11.8 to −3.0 | 34,342 | vvweight (validated-voter weight, for respondents whose registration was matched to voter-file records) and weight_cumulative | Cooperative Election Study |   |
| diff_white_black_late | +32.5 | percentage points of Democratic two-party vote share | age gap among white voters minus age gap among Black voters | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 and 2024 pooled | 95% CI 26.5 to 38.5 | 29,519 | weight_cumulative | Cooperative Election Study |   |
| diff_women_men_early | −9.6 | percentage points of Democratic two-party vote share | age gap among women minus age gap among men | two-party presidential voters aged 18 to 29 and aged 65 and over | 2008 and 2012 pooled | 95% CI −13.4 to −5.9 | 22,508 | weight_cumulative | Cooperative Election Study |   |
| diff_women_men_late | −3.8 | percentage points of Democratic two-party vote share | age gap among women minus age gap among men | two-party presidential voters aged 18 to 29 and aged 65 and over | 2020 and 2024 pooled | 95% CI −8.0 to 0.4 | 34,219 | weight_cumulative | Cooperative Election Study |   |
| fl_anes_vote_1911_1926_chg | −1.4 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1911 to 1926 | 1952 to 1996 | 95% CI −11.9 to 9.2 | 616 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1911_1926_first | +7.8 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1911 to 1926 | 1952 | 95% CI 2.0 to 13.6 | 453 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1911_1926_last | +6.5 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1911 to 1926 | 1996 | 95% CI −2.4 to 15.3 | 163 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1927_1942_chg | +2.5 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1927 to 1942 | 1956 to 2024 | 95% CI −10.2 to 15.1 | 382 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1927_1942_last | +4.6 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1927 to 1942 | 2024 | 95% CI −5.3 to 14.6 | 204 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1943_1958_chg | −12.9 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1943 to 1958 | 1972 to 2024 | 95% CI −20.3 to −5.5 | 1,558 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1943_1958_first | +15.6 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1943 to 1958 | 1972 | 95% CI 10.1 to 21.2 | 403 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1943_1958_last | +2.7 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1943 to 1958 | 2024 | 95% CI −2.1 to 7.5 | 1,155 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1959_1974_first | +0.6 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1959 to 1974 | 1984 | 95% CI −7.7 to 9.0 | 151 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1959_1974_last | −5.5 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1959 to 1974 | 2024 | 95% CI −10.5 to −0.5 | 1,061 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1975_1990_chg | −18.2 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1975 to 1990 | 2004 to 2024 | 95% CI −29.1 to −7.3 | 1,101 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1975_1990_first | +19.7 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1975 to 1990 | 2004 | 95% CI 10.1 to 29.3 | 137 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1975_1990_last | +1.5 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1975 to 1990 | 2024 | 95% CI −3.7 to 6.6 | 964 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_anes_vote_1991_present_chg | −10.5 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1991 to or later | 2016 to 2024 | 95% CI −21.7 to 0.6 | 629 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fl_ces_pid_1927_1942_chg | −9.6 | percentage points of the Democratic share of party identifiers | last cell's lead over other voters minus first cell's lead; different respondents | party identifiers (leaners included) born 1927 to 1942 | 2006 to 2024 | 95% CI −13.6 to −5.6 | 6,804 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_pid_1943_1958_chg | −1.7 | percentage points of the Democratic share of party identifiers | last cell's lead over other voters minus first cell's lead; different respondents | party identifiers (leaners included) born 1943 to 1958 | 2006 to 2024 | 95% CI −3.8 to 0.3 | 24,734 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_pid_1959_1974_chg | −7.2 | percentage points of the Democratic share of party identifiers | last cell's lead over other voters minus first cell's lead; different respondents | party identifiers (leaners included) born 1959 to 1974 | 2006 to 2024 | 95% CI −9.2 to −5.2 | 26,506 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_pid_1975_1990_chg | −4.8 | percentage points of the Democratic share of party identifiers | last cell's lead over other voters minus first cell's lead; different respondents | party identifiers (leaners included) born 1975 to 1990 | 2006 to 2024 | 95% CI −7.2 to −2.4 | 15,180 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_pid_1991_present_chg | −7.3 | percentage points of the Democratic share of party identifiers | last cell's lead over other voters minus first cell's lead; different respondents | party identifiers (leaners included) born 1991 to or later | 2010 to 2024 | 95% CI −13.9 to −0.7 | 9,188 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1927_1942_last | −13.9 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1927 to 1942 | 2024 | 95% CI −17.5 to −10.2 | 1,150 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1943_1958_chg | +0.8 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1943 to 1958 | 2008 to 2024 | 95% CI −1.5 to 3.0 | 20,481 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1959_1974_chg | −7.3 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1959 to 1974 | 2008 to 2024 | 95% CI −9.6 to −5.1 | 22,617 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1975_1990_chg | −9.1 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1975 to 1990 | 2008 to 2024 | 95% CI −11.7 to −6.5 | 13,015 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1975_1990_first | +16.6 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1975 to 1990 | 2008 | 95% CI 14.7 to 18.5 | 4,555 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1975_1990_last | +7.5 | percentage points of Democratic two-party vote share | cohort's Democratic share minus the share among voters born in other years in the same election | two-party presidential voters born 1975 to 1990 | 2024 | 95% CI 5.7 to 9.3 | 8,460 | weight_cumulative | Cooperative Election Study |   |
| fl_ces_vote_1991_present_chg | +5.9 | percentage points of Democratic two-party vote share | last cell's lead over other voters minus first cell's lead; different respondents | two-party presidential voters born 1991 to or later | 2012 to 2024 | 95% CI 0.1 to 11.7 | 5,030 | weight_cumulative | Cooperative Election Study |   |
| floor_n | 100 | respondents | definition of the suppression floor | floor for a published survey cell | all years |   |   | none (definition) | ANES Cumulative Data File |   |
| fs_anes_vote_1975_1990_first | 66.0% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters born 1975 to 1990 | 2004 | 95% CI 57.3% to 74.7% | 137 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fs_anes_vote_1975_1990_last | 55.6% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters born 1975 to 1990 | 2024 | 95% CI 51.3% to 60.0% | 964 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| fs_ces_vote_1975_1990_first | 66.3% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters born 1975 to 1990 | 2008 | 95% CI 64.6% to 68.0% | 4,555 | weight_cumulative | Cooperative Election Study |   |
| fs_ces_vote_1975_1990_last | 54.6% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters born 1975 to 1990 | 2024 | 95% CI 53.0% to 56.2% | 8,460 | weight_cumulative | Cooperative Election Study |   |
| grp_asian_late | +12.9 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, Asian | 2020 and 2024 pooled | 95% CI 2.5 to 23.4 | 883 | weight_cumulative | Cooperative Election Study |   |
| grp_black_late | −12.3 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, black | 2020 and 2024 pooled | 95% CI −17.7 to −6.8 | 3,055 | weight_cumulative | Cooperative Election Study |   |
| grp_hisp_chg | −16.8 | percentage points of Democratic two-party vote share | late-period age gap minus early-period age gap; different respondents | two-party presidential voters aged 18 to 29 and aged 65 and over, hispanic | 2008 and 2012 pooled to 2020 and 2024 pooled | 95% CI −28.3 to −5.2 | 3,763 | weight_cumulative | Cooperative Election Study |   |
| grp_hisp_early | +22.1 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, hispanic | 2008 and 2012 pooled | 95% CI 12.9 to 31.2 | 1,208 | weight_cumulative | Cooperative Election Study |   |
| grp_hisp_late | +5.3 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, hispanic | 2020 and 2024 pooled | 95% CI −1.7 to 12.3 | 2,555 | weight_cumulative | Cooperative Election Study |   |
| grp_men_chg | −7.1 | percentage points of Democratic two-party vote share | late-period age gap minus early-period age gap; different respondents | two-party presidential voters aged 18 to 29 and aged 65 and over, men | 2008 and 2012 pooled to 2020 and 2024 pooled | 95% CI −11.4 to −2.8 | 25,914 | weight_cumulative | Cooperative Election Study |   |
| grp_men_early | +27.0 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, men | 2008 and 2012 pooled | 95% CI 24.1 to 29.8 | 10,572 | weight_cumulative | Cooperative Election Study |   |
| grp_men_late | +19.9 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, men | 2020 and 2024 pooled | 95% CI 16.6 to 23.1 | 15,342 | weight_cumulative | Cooperative Election Study |   |
| grp_white_late | +20.2 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, white | 2020 and 2024 pooled | 95% CI 17.7 to 22.7 | 26,464 | weight_cumulative | Cooperative Election Study |   |
| grp_women_chg | −1.3 | percentage points of Democratic two-party vote share | late-period age gap minus early-period age gap; different respondents | two-party presidential voters aged 18 to 29 and aged 65 and over, women | 2008 and 2012 pooled to 2020 and 2024 pooled | 95% CI −4.9 to 2.3 | 30,813 | weight_cumulative | Cooperative Election Study |   |
| grp_women_early | +17.3 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, women | 2008 and 2012 pooled | 95% CI 14.9 to 19.7 | 11,936 | weight_cumulative | Cooperative Election Study |   |
| grp_women_late | +16.1 | percentage points of Democratic two-party vote share | Democratic share among voters aged 18 to 29 minus Democratic share among voters aged 65 and over | two-party presidential voters aged 18 to 29 and aged 65 and over, women | 2020 and 2024 pooled | 95% CI 13.4 to 18.7 | 18,877 | weight_cumulative | Cooperative Election Study |   |
| match_old_2020 | 87.4% | share of respondents | share with a positive validated-voter weight (registration matched to a voter-file record), unweighted count | two-party presidential voters aged 65 and over | 2020 |   | 11,895 | none (count) | Cooperative Election Study |   |
| match_old_2024 | 84.6% | share of respondents | share with a positive validated-voter weight (registration matched to a voter-file record), unweighted count | two-party presidential voters aged 65 and over | 2024 |   | 15,005 | none (count) | Cooperative Election Study |   |
| match_young_2020 | 66.9% | share of respondents | share with a positive validated-voter weight (registration matched to a voter-file record), unweighted count | two-party presidential voters aged 18 to 29 | 2020 |   | 4,360 | none (count) | Cooperative Election Study |   |
| match_young_2024 | 45.5% | share of respondents | share with a positive validated-voter weight (registration matched to a voter-file record), unweighted count | two-party presidential voters aged 18 to 29 | 2024 |   | 3,082 | none (count) | Cooperative Election Study |   |
| matched_minus_all | +7.2 | percentage points of Democratic two-party vote share | age gap among matched respondents minus age gap among all respondents, standard weight; seeded percentile bootstrap over respondents | two-party presidential voters aged 18 to 29 and aged 65 and over | 2024 | 95% CI 3.8 to 10.6 | 18,087 | weight_cumulative | Cooperative Election Study |   |
| n_anes_elections | 19 | elections | count of elections | ANES presidential election studies | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_anes_gap_pos | 7 | elections | count of elections | ANES presidential elections whose age-gap interval is above zero | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_anes_gap_pub | 16 | elections | count of elections | ANES presidential elections with both age cells above the floor | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_anes_noage | 649 | respondents | count of respondents | two-party presidential voters with no recorded age | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_anes_voters | 33,768 | respondents | count of respondents | two-party presidential voters with a known age | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_anes_voters_2024 | 3,933 | respondents | count of respondents | two-party presidential voters with a positive vote weight | 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| n_ces_pid_cohort_sig | 4 | cohorts | count of cohorts | CES birth cohorts whose party-identification lead has an interval for its change that excludes zero | 2006 to 2024 |   |   | none (count) | Cooperative Election Study |   |
| n_ces_pid_cohorts | 5 | cohorts | count of cohorts | CES birth cohorts | 2006 to 2024 |   |   | none (count) | Cooperative Election Study |   |
| n_ces_pid_waves | 10 | waves | count of waves | CES even-year waves | 2006 to 2024 |   |   | none (count) | Cooperative Election Study |   |
| n_ces_voters | 188,145 | respondents | count of respondents | two-party presidential voters with a known age | presidential elections 2008 to 2024 |   |   | none (count) | Cooperative Election Study |   |
| n_young_suppressed | 3 | elections | count of elections | ANES presidential elections whose youngest or oldest age cell is below the floor | presidential elections 1952 to 2024 |   |   | none (count) | ANES Cumulative Data File |   |
| neff_asian_late_young | 142 | respondents | Kish effective sample size | two-party presidential voters aged 18 to 29, Asian | 2020 and 2024 pooled |   | 569 | weight_cumulative | Cooperative Election Study |   |
| neff_black_young_2024 | 95 | respondents | Kish effective sample size | two-party presidential voters aged 18 to 29, Black | 2024 |   | 298 | weight_cumulative | Cooperative Election Study |   |
| three_anes_cross_section | −2.2 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on age (per decade), election fixed effects; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 1952 to 2024 | 95% CI −2.6 to −1.7 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| three_anes_same_age | +1.6 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on election year (per decade), fixed effect for each 4-year age band; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 1952 to 2024 | 95% CI 1.3 to 1.9 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| three_anes_same_cohort | +0.3 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on election year (per decade), fixed effect for each 4-year birth band; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 1952 to 2024 | 95% CI −0.3 to 0.8 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| three_anes_sumdiff | −0.8 | percentage points of Democratic two-party vote share per decade | cross-section slope plus same-age slope minus same-cohort slope; seeded respondent bootstrap interval | two-party presidential voters aged 18 to 73 | elections 1952 to 2024 | 95% CI −1.0 to −0.6 | 30,571 | weight_postelection where the file has one, otherwise weight (VCF0009z) | ANES Cumulative Data File |   |
| three_ces_cross_section | −4.3 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on age (per decade), election fixed effects; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 2008 to 2024 | 95% CI −4.6 to −4.1 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| three_ces_same_age | −1.2 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on election year (per decade), fixed effect for each 4-year age band; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 2008 to 2024 | 95% CI −1.8 to −0.5 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| three_ces_same_cohort | −5.2 | percentage points of Democratic two-party vote share per decade | slope of the Democratic share on election year (per decade), fixed effect for each 4-year birth band; weighted least squares, HC3 errors | two-party presidential voters aged 18 to 73 | elections 2008 to 2024 | 95% CI −5.9 to −4.6 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| three_ces_sumdiff | −0.3 | percentage points of Democratic two-party vote share per decade | cross-section slope plus same-age slope minus same-cohort slope; seeded respondent bootstrap interval | two-party presidential voters aged 18 to 73 | elections 2008 to 2024 | 95% CI −0.5 to −0.1 | 169,858 | weight_cumulative | Cooperative Election Study |   |
| weight_effect | +0.8 | percentage points of Democratic two-party vote share | age gap with the validated-voter weight minus age gap with the standard weight on the same matched respondents; seeded percentile bootstrap | two-party presidential voters whose registration was matched to voter-file records, aged 18 to 29 and aged 65 and over | 2024 | 95% CI −3.0 to 4.8 | 18,087 | vvweight (validated-voter weight, for respondents whose registration was matched to voter-file records) and weight_cumulative | Cooperative Election Study |   |
| young_match_gap_2020 | +3.0 | percentage points of Democratic two-party vote share | Democratic share among matched respondents minus Democratic share among unmatched respondents | two-party presidential voters aged 18 to 29 | 2020 | 95% CI −1.1 to 7.1 | 4,360 | weight_cumulative | Cooperative Election Study |   |
| young_match_gap_2024 | +13.8 | percentage points of Democratic two-party vote share | Democratic share among matched respondents minus Democratic share among unmatched respondents | two-party presidential voters aged 18 to 29 | 2024 | 95% CI 7.8 to 19.7 | 3,082 | weight_cumulative | Cooperative Election Study |   |
| young_matched_2024 | 68.2% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 18 to 29, registration matched to voter-file records | 2024 | 95% CI 64.1% to 72.4% | 1,403 | weight_cumulative | Cooperative Election Study |   |
| young_unmatched_2024 | 54.5% | percent of the two-party presidential vote | weighted Democratic share | two-party presidential voters aged 18 to 29, registration unmatched to voter-file records | 2024 | 95% CI 50.2% to 58.8% | 1,679 | weight_cumulative | Cooperative Election Study |   |

## Definitions

- Percentage point: The unit for the difference between two percentages. A change from one share to another is stated in points, not in percent, so that absolute and relative change are not confused.
- Cohort: People born in the same period, such as the same decade. Comparing cohorts shows whether a difference comes from when people were born, as distinct from their age or the year they were surveyed.
- Partisan leaner: A respondent who first says they are independent but, when asked, says they lean toward one party. Most figures group leaners with the party they lean toward, and each chapter says which grouping it uses.
- Confidence interval: A range around an estimate that would contain the true value in 95% of repeated samples if the sampling model held. The book reports 95% intervals unless it says otherwise.
- Effective sample size: The number of equally weighted respondents that would give the same precision as the weighted sample. It is smaller than the raw count when the weights vary a lot, and it sets how wide the confidence interval is.
- Survey weights: Numbers that scale each respondent so the sample matches the population on known traits such as age, race, education and region. A weighted average counts a respondent with a large weight for more than one with a small weight.
- Survey mode: How respondents were interviewed: in person, by phone, on paper or online. Mode can change answers, so a change in mode can look like a change in opinion.
- Linear probability model: A regression of a yes-or-no outcome on predictors, fitted by least squares so that each coefficient is a change in the probability of yes. The book weights it and reports robust standard errors.

## Methods

Samples: ANES Cumulative Data File respondents in the 19 presidential elections from 1952 to 2024 who reported voting for the Democratic or the Republican candidate (two-party voters) and have a recorded age of 18 or older (33,768 respondents; 649 other two-party voters have no age and are outside every age cell but inside the cohort cells when their cohort is known; a handful of 17-year-olds are left out), and party identifiers in the same presidential-election years (44,932 respondents with a known age); CES cumulative file respondents who reported such a vote in 2008, 2012, 2016, 2020 and 2024 (188,145) and party identifiers in the even-year waves 2006 to 2024 (450,325). voted_dem_pres equal to 0 in the ANES also holds third-party voters, so the vote is built from voted_dem_pres equal to 1 and voted_rep_pres equal to 1. Weights: ANES vote shares use weight_postelection in the years where the file has one (1996, 2000, 2004, 2008, 2016, 2020, 2024), otherwise weight (VCF0009z), the rule used by the two-coalitions and gender-gap chapters; ANES party identification uses weight (VCF0009z); the ANES interview-mode estimates use weight_ftf on face-to-face respondents and weight_web on web respondents (2012, 2016 and 2024; the 2020 study has no mode weights and no in-person interviews); CES estimates use weight_cumulative, the cumulative-file weight defined for all five elections, which is proportional within each election to the single-wave pre-election weight; the vote is a post-election item, and the post-election weight (weight_post), which exists for 2012, 2016 and 2020 only, is used for a sensitivity check; the matched-voter rows use vvweight, the weight for validated registered voters (respondents whose registration was matched to a voter-file record, not whose vote was validated), which the file holds for 2018, 2020, 2022 and 2024 and which equals a constant multiple of weight_cumulative in 2020. ANES 2012 uses the full-sample weight because the file has no post-election weight for that study; in 2024, a share of respondents (panel and paper cases) have no interview-mode weight and are outside the mode cells. Groups: age 18 to 29, 30 to 44, 45 to 64 and 65 and over from age in years (the CES vote figure splits the youngest group at 24 and 25); birth cohort is the ANES cohort variable (16-year groups; cohort cells include every voter with a known cohort) and, in the CES, the same groups from reported birth year; party identification is Democratic (pid7 or pid_7pt 1 to 3) against Republican (5 to 7), pure independents excluded. Estimands: a share is a weighted mean of a 0/1 outcome; the age gap is the share among the youngest group minus the share among the oldest; a cohort's lead is its share minus the share among all other voters with a known cohort in the same election (a disjoint group, so the two shares are independent); a change is a difference of two independent estimates from different elections. Intervals: 95%. Shares and differences within one election use the Kish effective sample size and a normal approximation, and combine the standard errors of independent groups in quadrature. The 2024 CES difference between the gap among matched respondents and the gap among all voters, the difference between the two weights on the same matched respondents, and the difference between the change in the gap from 2020 to 2024 among all voters and the same change among matched respondents are seeded percentile bootstraps over respondents, resampling within each year (1,000 replicates, seed 12345), because those estimates share respondents. The certified benchmark is the two-party share of the state presidential returns (full counts). Three comparisons: weighted least squares with HC3 errors on voters aged 18 to 73 (ANES 30,571, CES 169,858 respondents): the vote on age in decades with election fixed effects; on election year in decades with fixed effects for 4-year age bands; and on election year in decades with fixed effects for 4-year birth bands. The sum of the first two slopes minus the third has a seeded respondent bootstrap interval that recomputes the three slopes on each resample. Age-period-cohort model: voters aged 18 to 73 are grouped into 14 age bands of 4 years and the presidential elections (4 years apart, so birth cohort is the election index minus the age-band index); the 0/1 vote is regressed on an effect for every age band, election and cohort by weighted least squares on the cell means (the linear probability model), taking the minimum-norm solution. Adding a straight line to the age and cohort effects and subtracting one from the election effects leaves every fitted cell unchanged, and each constraint chooses the shift that sets the straight-line component of one effect to zero (no trend across birth years, across elections or across ages). The largest difference in fitted cell means across the three constraints is 2.2e-14 percentage points in the ANES and 1.1e-14 in the CES. Intervals for the model are percentile intervals from 1,000 respondent-level bootstrap replicates (seed 12345). Suppression: a published cell needs at least 100 respondents and a Kish effective sample of at least 100; a suppressed cell is a row with no value, so no line is drawn across it. All intervals are model based. The CES is an opt-in panel, so its intervals leave out how respondents joined the panel, and the ANES intervals ignore clustering and stratification. Survey mode: the ANES mixes face-to-face and web interviews in 2012, 2016 and 2024 and used no in-person interviews in 2020; the CES is an online panel in every year.

## What these data cannot show

- The surveys interview different people in each election, so a cohort line does not follow anyone.
- It mixes people who changed, people who joined or left the sample (a cohort is smaller at older ages and its youngest members enter as they turn eighteen), and the effects of age and election.
- A panel study that re-interviews the same voters separates a person's change from the replacement of cohorts, and it still cannot separate the effect of age from the effect of the election in which the person is re-interviewed.
- The ANES 2024 Time Series holds a sample interviewed in 2016, 2020 and 2024 and the CES has panel files, but the earlier waves of both are not in the data store, so no panel evidence appears here.
- The chapter chooses no constraint for the age-period-cohort model and reports the range.
- A model with more structure can give a narrower answer only by assuming that structure, and the surveys do not test it.
- The generation labels in the literature summarize cohort differences, and they do not explain why those differences arise.
- The data hold no measure of the events, campaigns or candidates that might have shaped any cohort.
- The vote is the respondent's report, restricted to two-party voters.
- The ANES Democratic share exceeds the certified count in 2020 and 2024 by more than its interval, and the excess is largest among voters sixty-five and older.
- Its age gaps therefore rest on a sample that departs from the count most in the oldest group.
- The CES share is close to the count in 2024.
- Neither survey can be checked against an official count by age group.
- The two surveys disagree about 2024, and the explanations offered here, who is matched to voter records and interview mode, cannot be settled with these files.
- The ANES youngest-group cells are small, 3 elections have none to publish, 649 two-party voters have no recorded age and fall outside every age cell, and age is top-coded at eighty in 2020 and 2024.
- The 2012, 2016 and 2024 ANES samples mix modes and 2020 has no mode weights, so a change between those elections can include a change of mode.
- The CES is an opt-in panel and its intervals leave out how respondents joined it.
- The ANES intervals ignore clustering and stratification, so they can be too narrow or too wide.
- The chapter reports many comparisons, and no interval is adjusted for that.
- Cohorts are sixteen-year groups, and a finer grouping could show movements that these groups average away.

## References

1. Glenn, Norval D. (1976). Cohort Analysts' Futile Quest: Statistical Attempts to Separate Age, Period and Cohort Effects. American Sociological Review 41(5): 900-904. https://doi.org/10.2307/2094738
2. Mason, Karen Oppenheim; Mason, William M.; Winsborough, H. H.; Poole, W. Kenneth (1973). Some Methodological Issues in Cohort Analysis of Archival Data. American Sociological Review 38(2): 242-258. https://doi.org/10.2307/2094398
3. Kish, Leslie (1965). Survey Sampling. John Wiley and Sons.
4. Converse, Philip E. (1969). Of Time and Partisan Stability. Comparative Political Studies 2(2): 139-171. https://doi.org/10.1177/001041406900200201
5. Ghitza, Yair; Gelman, Andrew; Auerbach, Jonathan (2023). The Great Society, Reagan's Revolution, and Generations of Presidential Voting. American Journal of Political Science 67(3): 520-537. https://doi.org/10.1111/ajps.12713
6. Fosse, Ethan; Winship, Christopher (2019). Analyzing Age-Period-Cohort Data: A Review and Critique. Annual Review of Sociology 45: 467-492. https://doi.org/10.1146/annurev-soc-073018-022616

## Provenance

- Pipeline version: 1.0.0
- Build script: book3/chapters/age-and-generation/build.py (sha256 464249535298f8468d0e6afdbf15063a7e12b1dd4df6b14cca097b2c4e42cb18)
- Built on: 2026-10-03
- Site commit: 16414b2c7257546a7042d0b1734657f208999f60

Inputs:

| File | Size (bytes) | SHA-256, first 1 MB | SHA-256, last 1 MB |
| --- | ---: | --- | --- |
| data/anes/anes_cdf_clean.parquet | 15,640,720 | b3f0c2d8ae5673b2c40cf6df71318ea3f712cd845c4f1aad0460f28d1b022643 | 04f06dae56b65649291caf6cf77aab9767d9c92d0c2669c6d3655d9063970583 |
| data/cces/cces_clean.parquet | 53,454,868 | 9430e88b3196c9ca2250bdda1908d3920e80e276ca0c529c514e2fc2bdd00806 | f61097c727c38fd8d7c8e53fe86935fb626f351a64d99ccb1ae0b56715b2c405 |
| data/state/1976-2024-president.csv | 514,108 | 9936410a6dd4ecc8be7fe202c6dff5b5f8fee59d88f35ab542ed12879941dcb7 | 9936410a6dd4ecc8be7fe202c6dff5b5f8fee59d88f35ab542ed12879941dcb7 |

Outputs:

| File | SHA-256 |
| --- | --- |
| facts.json | 128cdd0930f6ed19eed41a33480562b059c792bc19df2d79f574ea54a0db8b1c |
| figures/age_gap.json | 5c68dc790d174e40b5942167ed4877fd5c9860875e0866b601acd7b692378c48 |
| figures/age_gap_groups.json | a6fbbeeaf3da525999e56335a984b3f2d371fcbff9d85c9104d419e5a0ec0768 |
| figures/apc_profiles.json | 50df509c6ca3b0a747dbd8f0da1df52fd89b337f7bea9d9e184de30285f7ffed |
| figures/cohort_first_last.json | 9ca8506539efb9b69832503d93a8dc15123be4a838855dbfada9c9ec6746bf17 |
| figures/cohort_lines.json | df49170b05b6c3bf340df6523aa466ffc631fa9a43ddfa99dab21324e18f37c0 |
| figures/pid_by_age.json | d04a402e6c42b7bf46a06eca297e4a68fb1a60990bdd39f7a1bb0d59b2fddea6 |
| figures/three_comparisons.json | d9608a4eb7f3a817e25f6da4ff406f6ecb169622f1262abf789eacdbf68dc350 |
| figures/vote_by_age_anes.json | 1efb7cd1caa19e1fe4b012835f766c10c860ce2bb86636d9fe590adadf8094e0 |
| figures/vote_by_age_ces.json | f1c1b73367fc98556f978d4c772bf5b321a5fd0dac89cede73616bb224ed007f |
| meta.json | 0483e6a8787119c2001a886b95bbd41d2fb3e8613df60a304b2b15a2fa0523d9 |
| refs.json | 705f7576b3fa58e7bc681fea08d82f7e611c2ac14d08129cf76cc82b716f2e08 |

## Machine formats

- Report (HTML): https://vishalsingh.org/politics/age-and-generation/report
- Report (Markdown): https://vishalsingh.org/politics/age-and-generation/report.md
- Every estimate (JSON): https://vishalsingh.org/politics/report/age-and-generation/facts.json
- Table 1, figure "vote_by_age_anes" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/vote_by_age_anes.json
- Table 2, figure "vote_by_age_ces" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/vote_by_age_ces.json
- Table 3, figure "age_gap" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/age_gap.json
- Table 4, figure "pid_by_age" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/pid_by_age.json
- Table 5, figure "cohort_lines" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/cohort_lines.json
- Table 6, figure "cohort_first_last" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/cohort_first_last.json
- Table 7, figure "age_gap_groups" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/age_gap_groups.json
- Table 8, figure "three_comparisons" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/three_comparisons.json
- Table 9, figure "apc_profiles" (JSON): https://vishalsingh.org/politics/report/age-and-generation/figures/apc_profiles.json
- Index of every report: https://vishalsingh.org/politics/llms.txt; all reports in one file: https://vishalsingh.org/politics/llms-full.txt