Chapter 2.4 · The vanishing cradle · Report

Where births are falling

Births in the counties that CDC WONDER identifies fell 4.6% from 2018 to 2024, by 5.6% in the least deprived quartile of counties and 7.3% in the most deprived.

Author: Vishal Singh
Affiliation: NYU Stern
Published: 9 October 2026

Every estimate of the chapter with its interval and every figure as a table, generated from the chapter's data files. Table n of this report is figure n of the chapter. The same report as Markdown: report.md.

Identification

Title

Where births are falling

Label

The vanishing cradle

Chapter

2.4 (Part II, Birth; An American life)

Question

Which counties lost the most births between 2018 and 2024, and how did the age of mothers change in those places?

Dek

Births in the counties that CDC WONDER identifies fell 4.6% from 2018 to 2024, by 5.6% in the least deprived quartile of counties and 7.3% in the most deprived.

Grain

counties

Status

published

Published

9 October 2026

Updated

not revised

Data sources

CDC WONDER natality. CDC WONDER natality, county totals and county by mother's age, births in 2018 to 2024 (consolidated pulls); 2024 is final; years: 2018-2024; weights: births in each county (pooled ratios of sums); changes and shares pooled over counties
Area Deprivation Index. Neighborhood Atlas Area Deprivation Index 2023 (v4.0.1), tract national rank, averaged to counties with 2019-2023 tract population; years: 2023 release (version 4.0.1; built on ACS 2019-2023); weights: 2019-2023 tract population

Canonical URL

https://vishalsingh.org/zipcode/where-births-are-falling

Markdown

https://vishalsingh.org/zipcode/where-births-are-falling/report.md

BibTeX

@misc{singh2026wherebirthsarefalling,
  author = {Singh, Vishal},
  title = {Where births are falling},
  year = {2026},
  url = {https://vishalsingh.org/zipcode/where-births-are-falling},
  note = {In ZIP Code Destiny. Published 9 October 2026.}
}

Principal estimates

The facts the dek and the opening prose cite, in order of appearance. Every fact is in the table of all estimates below.

Estimand	Population	Period	Value	Interval	n	Weights	Source	Fact id
fall in the count of births from 2018 to 2024	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018 to 2024	4.6%			none (full count)	CDC WONDER natality	decline_named
fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the least deprived quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	5.6%	95% CI 2.8% to 8.2%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	decline_q1
fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the most deprived quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	7.3%	95% CI 5.8% to 8.8%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	decline_q4
count of counties	counties that WONDER natality identifies in every year from 2018 to 2024 and that have births	births in 2018 to 2024	578			none (full count)	CDC WONDER natality	counties_used
count of live births	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018	3.02 million			none (full count)	CDC WONDER natality	births_named_2018
count of live births	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2024	2.88 million			none (full count)	CDC WONDER natality	births_named_2024
population size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)	counties that CDC WONDER natality identifies	births in 2018 to 2024	100,000			none (definition)	CDC WONDER natality	wonder_threshold
share of births in the named counties	live births in the 50 states and DC	2024	79.4%			none (full count)	CDC WONDER natality	share_named_2024
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census South region	births in 2018 and 2024	0.0%	95% CI −1.7% to 1.8%	232 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	region_south
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census Midwest region	births in 2018 and 2024	−8.4%	95% CI −10.4% to −6.3%	137 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	region_midwest
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census West region	births in 2018 and 2024	−7.9%	95% CI −10.7% to −5.0%	99 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	region_west
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census Northeast region	births in 2018 and 2024	−5.0%	95% CI −7.3% to −2.5%	110 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	region_northeast
fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the second quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	2.6%	95% CI −0.6% to 5.3%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	decline_q2
fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the third quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	3.1%	95% CI 1.6% to 4.5%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	decline_q3
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 15 to 19 in the named counties that publish the band in both years	births in 2018 and 2024	24.6%	95% CI 22.7% to 26.5%	577 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	fall_1519
age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)	15 to 19			none (definition)	CDC WONDER natality	band_1519
pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 40 to 44 in the named counties that publish the band in both years	births in 2018 and 2024	19.5%	95% CI 17.0% to 22.3%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality	rise_4044
age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)	40 to 44			none (definition)	CDC WONDER natality	band_4044

Findings

Births in the 578 counties that CDC WONDER identifies fell from 3.02 million in 2018 to 2.88 million in 2024, a decline of 4.6%. These counties have 100,000 or more residents in the population vintage WONDER uses, and they record 79.4% of the births in the United States in 2024.

Pooled over counties, births changed by 0.0% (95% CI −1.7% to 1.8%) in the South, −8.4% (95% CI −10.4% to −6.3%) in the Midwest, −7.9% (95% CI −10.7% to −5.0%) in the West and −5.0% (95% CI −7.3% to −2.5%) in the Northeast. Pooled births fell by 5.6% (95% CI 2.8% to 8.2%) in the least deprived quartile of these counties, by 2.6% and 3.1% in the second and third quartiles, and by 7.3% (95% CI 5.8% to 8.8%) in the most deprived. The losses do not rise in steps with deprivation, and region and deprivation overlap, so the chapter looks at them together.

The ages of mothers shifted too. Between 2018 and 2024 births fell by 24.6% among mothers aged 15 to 19 and rose by 19.5% among mothers aged 40 to 44.

Everything in this chapter is a count of births in a county or a share of those births. A birth rate divides births by the women who could have had them, and the files behind this book have no county counts of women by age, so the chapter reports counts and shares and no rates. The babies in these counties are the subject of Chapter 2.1, Birthweight and preterm birth, which asks how heavy they were at birth, and of Chapter 2.2, Infant mortality, which follows them through the first year.

Births have not returned to their 2018 level

Births in the named counties fell from 2018 to 2020 and rose through 2022 (Table 1). They fell again to a low in 2023, when they were 5.5% below 2018, and rose 0.9% in 2024. In 2020 they were 4.8% below 2018, and by 2024 they were still 4.6% below.

WONDER pools the births of every smaller county in a state into one row, 49 rows in all. Those rows record 0.77 million births in 2018 and 0.75 million in 2024, a decline of 3.0%, so the named counties lost a larger share of their births than the rest of the country combined. Across the whole country births fell from 3.79 million to 3.63 million, a decline of 4.3%. The count for 2024 is the one in the final report of the National Center for Health Statistics, and 2024 is final in these data.[1]

Birth rates in the United States have been falling since the Great Recession. Kearney, Levine and Pardue document that birth rates fell between 2007 and 2020 across many groups of women, and they find that the recession explains only part of the early decline.[2] This chapter starts in 2018 and describes where the recent loss fell.

Table 1. Births in the named counties fell 4.6% from 2018 to 2024 with a low in 2023, a larger fall than the 3.0% in all other counties

The 578 named counties are the counties that WONDER identifies in every year from 2018 to 2024 and that have births in every year. WONDER lists two more county identifiers in every year, Cape May County, New Jersey, and Portsmouth city, Virginia. It gives them no births because it folded them into their state's pooled row, so they are left out. Every named county appears in every year from 2018 to 2024, so no county drops out of the panel by entering or leaving WONDER's list.

The selection is by size as WONDER measured it. WONDER applies its threshold of 100,000 residents to an earlier population estimate than the 2020 Census. By 2020 Census population, 27 counties outside Connecticut that have 100,000 or more residents are still in the pooled rows, among them Sumter County, Florida, Gallatin County, Montana, and Flagler County, Florida. In the other direction, one named county, Ashtabula County, Ohio, is below the line. The staged atlas has no 2020 count for Connecticut, whose counties are all named. Counties that grew past the line after WONDER's estimate therefore sit in the pooled rows. The comparison of the 3.0% decline there with the 4.6% decline in the named counties compares two groups defined by an earlier population estimate and not by size today.

The named counties record 79.7% of births in 2018 and 79.4% in 2024, and the smallest of them recorded at least 613 births in every year. County results in this chapter describe these counties and not the country. The pooled rows lost fewer births, with the caveat that they include counties that now exceed the line.

Births held up in the South and fell elsewhere

The Census Bureau groups states into the Northeast, the Midwest, the South and the West. The South, which has 16 states and the District of Columbia, holds 232 of the named counties, or 40.1%. Pooled over its counties, the South's births changed by 0.0% (95% CI −1.7% to 1.8%) from 2018 to 2024, an interval that includes zero. Births in the Midwest changed by −8.4% (95% CI −10.4% to −6.3%), in the West by −7.9% (95% CI −10.7% to −5.0%) and in the Northeast by −5.0% (95% CI −7.3% to −2.5%), so the intervals for those three regions lie below zero.

The South's change is higher than the Northeast's by 5.0 percentage points (95% CI 2.0 percentage points to 7.9 percentage points), than the Midwest's by 8.4 percentage points (95% CI 5.7 percentage points to 11.1 percentage points) and than the West's by 7.9 percentage points (95% CI 4.3 percentage points to 11.3 percentage points). The intervals come from a bootstrap that resamples whole counties, so they show how much a region's pooled change depends on which counties it holds.

Table 2. Of the 58 counties with the largest gains in births, 43 are in the South, which holds 40.1% of the named counties

The map (Table 2) shows the same split county by county. The top tenth of counties by change, with gains of 10.2% or more, holds 58 counties, and 43 of them are in the South. The bottom tenth, with declines of 13.6% or more, holds 58 counties, and 13 are in the South.

Counted one county at a time, 65.7% of the named counties lost births. Births were lower in 2024 than in 2018 in 380 counties, higher in 197 and the same in one.

The median county lost 3.8%, and from the 5th to the 95th percentile of counties, changes run from a decline of 16.5% to a gain of 19.9%. The pooled decline of 4.6% is larger than the median county's because the pooled figure weights each county by its births and the median counts each county once.

Table 3. The ten largest gains in births are all in the South, and the ten largest declines are spread across every Census region

Table 3 lists the ten counties with the largest gains and the ten with the largest declines. Beyond the middle of the distribution, where changes from the 5th to the 95th percentile of counties run from a decline of 16.5% to a gain of 19.9%, the extremes are a decline of 23.9% in St. Louis city, Missouri, and a gain of 67.6% in Kaufman County, Texas. All of the gains are in the South, in Texas, North Carolina and Georgia. The declines are spread across every region and include St. Louis city, Missouri, Hinds County, Mississippi, Humboldt County, California, San Francisco County and Orleans Parish, Louisiana. Every county listed had at least 987 births in 2018. Small counts move more from year to year by chance, so the order within each group is less stable than the groups themselves.

A county's births change when women have fewer children, when the number of women of childbearing age changes, or both, and these data cannot separate them. WONDER places a birth in the mother's county of residence, so a county that adds young families counts their births, and a gain in a fast-growing county may reflect arrivals as much as larger families.

The most deprived counties lost more births than the middle quartiles

To place counties on a deprivation scale, each census tract carries its Area Deprivation Index national rank, which orders neighborhoods by deprivation, with a higher rank meaning more deprived.[3] A tract's rank is the unweighted mean of the ranks of its block groups, and a county's rank is the average of its tracts' ranks, weighted by tract population, the measure used in Chapter 2.1, Birthweight and preterm birth. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation.

By 2024 pooled births in the most deprived quartile were 7.3% (95% CI 5.8% to 8.8%) below 2018 (Table 4). All four quartiles fell to 2020. In 2021 births in the other three quartiles rose and births in the most deprived quartile did not. Its pooled change was −0.3% (95% CI −0.8% to 0.1%), an interval that includes zero, and the other quartiles rose by more, by 1.9 percentage points (95% CI 1.0 percentage points to 3.0 percentage points) in the least deprived quartile, 2.5 percentage points (95% CI 1.4 percentage points to 3.6 percentage points) in the second and 1.3 percentage points (95% CI 0.5 percentage points to 2.2 percentage points) in the third.

The second and third quartiles lost 2.6% (95% CI −0.6% to 5.3%) and 3.1% (95% CI 1.6% to 4.5%) from 2018 to 2024, and the middle quartiles together lost 2.8% (95% CI 1.1% to 4.5%). The most deprived quartile therefore lost 4.5 percentage points (95% CI 2.3 percentage points to 6.7 percentage points) more than the middle quartiles. The least deprived quartile lost 5.6% (95% CI 2.8% to 8.2%). It lost 2.7 percentage points (95% CI −0.5 percentage points to 5.9 percentage points) more than the middle quartiles and 1.7 percentage points (95% CI −1.2 percentage points to 5.0 percentage points) less than the most deprived quartile, and both intervals include zero, so the data do not place it with either.

A single slope does not summarize the pattern. Regressing each county's change on its deprivation rank gives +0.5 percentage points (95% CI −0.2 percentage points to 1.2 percentage points) per ten ranks when counties are weighted by their births and −0.7 percentage points (95% CI −1.1 percentage points to −0.3 percentage points) when each county counts once. The sign depends on the weights, and only the unweighted interval excludes zero.

Table 4. Births in 2024 were below 2018 in all four quartiles of counties, by 5.6% in the least deprived and 7.3% in the most deprived, and in 2021 the other three quartiles rose by more than the most deprived

Region and deprivation overlap. Of the counties in the most deprived quartile, 45% are in the South, against 24% of the counties in the least deprived quartile. Table 5 splits the quartiles by region. The most deprived quartile lost births in every region: 9.3% (95% CI 6.6% to 11.8%) in the Northeast, 9.2% (95% CI 6.3% to 11.6%) in the Midwest, 5.0% (95% CI 2.9% to 7.0%) in the South and 9.3% in the West. The West's most deprived quartile holds only 5 counties, all of which lost births. A bootstrap over so few counties is mechanical, so no interval is printed for it.

In the South the other three quartiles together changed by +1.1% (95% CI −0.9% to 3.4%), which is higher than the change in the South's most deprived quartile by 6.1 percentage points (95% CI 3.2 percentage points to 9.0 percentage points). The South's flat total therefore combines a loss in its most deprived counties with no clear change elsewhere.

Table 5. The most deprived quartile of counties lost births in every Census region, and in the South the other three quartiles show no clear loss

These are patterns across counties and describe groups of births, not the mothers in any one county. The index measures neighborhoods averaged to counties, and it understates deprivation in high-cost cities, so some counties in the least deprived quartile hold neighborhoods that are more deprived than their rank suggests.

From 2018 to 2024, births fell in every five-year band of mothers aged 15 to 29, by 24.6% (95% CI 22.7% to 26.5%) among mothers aged 15 to 19, by 16.6% (95% CI 15.0% to 18.3%) among mothers aged 20 to 24 and by 11.2% (95% CI 9.6% to 12.9%) among mothers aged 25 to 29. Births to mothers aged 30 to 34 changed by +1.0% (95% CI −0.6% to 2.6%), an interval that includes zero. Births rose by 9.2% (95% CI 7.3% to 11.0%) among mothers aged 35 to 39 and by 19.5% (95% CI 17.0% to 22.3%) among mothers aged 40 to 44 (Table 6).

As shares of births to mothers aged 15 to 44, mothers aged 15 to 24 went from 21.8% (95% CI 21.0% to 22.7%) to 18.7% (95% CI 18.0% to 19.5%), a fall of 3.1 percentage points (95% CI 2.9 percentage points to 3.3 percentage points). Mothers aged 35 to 44 went from 19.7% (95% CI 18.9% to 20.5%) to 22.9% (95% CI 22.1% to 23.8%), a rise of 3.2 percentage points (95% CI 3.1 percentage points to 3.4 percentage points). The shift continues a rise in the mean age of mothers that the National Center for Health Statistics documented for every birth order from 2000 to 2014.[4]

Table 6. Births fell for mothers aged 15 to 29, changed little for mothers aged 30 to 34 and rose for mothers aged 35 to 44 from 2018 to 2024

WONDER splits each county's births by the mother's age in nine bands. Six of them, the bands from 15 to 19 through 40 to 44, are published for nearly every county and year. Of the 24,276 county-year cells for those bands, WONDER withholds 11. Each holds fewer than 10 births, so together they hold at most 99 births, against 20.4 million in published cells.

The other three bands, mothers under 15 and mothers 45 and over, are mostly withheld, with 6,594 of 12,138 cells missing. The published cells hold 0.26% of births and the withheld ones at most 0.29%. The chapter therefore leaves all three bands out and compares mothers aged 15 to 44. A withheld cell is missing, never zero, and nothing is recovered from county totals.

These are births and not birth rates. A fall in births to mothers aged 15 to 19 can mean fewer births per teenager or fewer teenagers in the county, and the files behind this book have no county counts of women by age. A different measure of teen births, for women who grew up in each census tract, is in Chapter 4.2, Teen births.

The age mix differs more across counties than it changed

In 2018 the share of births to mothers aged 15 to 24 was 17.0% (95% CI 15.6% to 18.3%) in the least deprived quartile of counties and 30.9% (95% CI 29.9% to 32.1%) in the most deprived, a gap of 14.0 percentage points (95% CI 12.3 percentage points to 15.8 percentage points). In 2024 the shares were 14.5% (95% CI 13.4% to 15.5%) and 26.9% (95% CI 25.8% to 28.0%), a gap of 12.4 percentage points (95% CI 11.0 percentage points to 14.0 percentage points).

For mothers aged 35 to 44 the 2018 shares were 24.3% (95% CI 23.1% to 25.5%) in the least deprived quartile and 13.0% (95% CI 12.5% to 13.5%) in the most deprived, a gap of 11.3 percentage points (95% CI 10.0 percentage points to 12.5 percentage points). In 2024 they were 27.8% (95% CI 26.4% to 29.2%) and 15.8% (95% CI 15.1% to 16.5%), a gap of 12.0 percentage points (95% CI 10.5 percentage points to 13.5 percentage points) (Table 7).

Every quartile moved in the same direction. The share of births to mothers aged 15 to 24 fell by 2.5 percentage points (95% CI 1.9 percentage points to 3.0 percentage points) in the least deprived quartile and by 4.0 percentage points (95% CI 3.7 percentage points to 4.4 percentage points) in the most deprived. The share to mothers aged 35 to 44 rose by 3.5 percentage points (95% CI 3.1 percentage points to 3.9 percentage points) and by 2.8 percentage points (95% CI 2.5 percentage points to 3.1 percentage points). The share of young mothers fell by 1.5 percentage points (95% CI 0.9 percentage points to 2.2 percentage points) more in the most deprived quartile. The share of older mothers rose by 0.7 percentage points (95% CI 0.3 percentage points to 1.2 percentage points) more in the least deprived quartile, so the shifts differ in size. Each is much smaller than the gap between quartiles.

Table 7. In every quartile of county deprivation the share of births to older mothers rose and the share to younger mothers fell, and the differences between quartiles are larger than those changes

Counties that lost the most births lost them among younger mothers

The counties that lost the most births lost them among mothers under 35. Sorting counties by the change in their total births shows where in the age range the loss fell (Table 8). The 144 counties in the quarter with the largest declines, falls of 8.8% or more, lost 13.5% of their births in all. Their births fell by 32.9% among mothers aged 15 to 19, by 25.1% among mothers aged 20 to 24, by 21.1% among mothers aged 25 to 29 and by 8.8% among mothers aged 30 to 34. Births to mothers aged 35 to 39 changed by −0.1%, and births to mothers aged 40 to 44 rose by 9.6%.

The 145 counties in the quarter with the largest gains, gains of 2.6% or more, added 11.2% in all. Births in those counties fell by 13.0% among mothers aged 15 to 19 and by 4.0% among mothers aged 20 to 24, and rose in every older band, from 5.8% among mothers aged 25 to 29 to 39.3% among mothers aged 40 to 44.

Table 8. Counties with the largest declines in births lost births at every age under 35, and counties with the largest gains added births at every age from 25

The groups are formed on the change in total births, so the figure splits each group's change by age and does not test an explanation. A separate question is whether a county's age mix predicts its change. Suppose every age band in a county changed at the all-county rate. The county's 2018 mix would then imply a change in births to mothers aged 15 to 44 between a fall of 8.9% and a fall of 1.3% at the 5th and 95th percentiles of counties. The observed changes run over a much wider range, from a fall of 16.6% to a gain of 19.8%.

The implied and observed changes have a correlation of −0.16 (95% CI −0.26 to −0.06) across 577 counties when counties are weighted by their births and −0.03 (95% CI −0.11 to 0.04) when each counts once. The one county that withholds an age cell is left out. A county's 2018 age mix therefore does not account for which counties lost births. The weighted correlation is small and negative, so counties whose mix implied larger falls lost slightly less.

What these data cannot show

The chapter reports counts and shares of births and no rates. A birth rate needs the number of women of each age as its denominator, and the files staged for this book hold the total population of counties and tracts but not women by age. A fall in births to mothers aged 20 to 24 can mean fewer births per woman, fewer women in that age group, or both, and so can a gain. County population estimates by age and sex from the Census Bureau would supply the denominator for age-specific rates. Births are counted in the mother's county of residence, so the map is not a map of fertility.

County results describe the 578 counties that WONDER identifies, those with 100,000 or more residents in its population vintage. They hold 79.4% of births in 2024, and they are not a sample of the country. The pooled rows lost fewer births, although those rows include counties that now exceed the line. WONDER's county files used here have no cut by the mother's race or Hispanic origin, so the chapter cannot say whether the shift in mothers' ages differs by group.

The deprivation comparison is descriptive. The Area Deprivation Index describes neighborhoods in 2019 to 2023 and is averaged to counties, and region and deprivation overlap. The comparison of quartiles says nothing about why births fell in any county. It is an ecological pattern, and it need not hold for the people inside the counties. The comparison of 2018 with 2024 uses the endpoint years only. A county with few births moves from year to year by chance, so a county's direction of change is better established than its rank among the named counties.

Tables

Table 1. Births in the named counties fell 4.6% from 2018 to 2024 with a low in 2023, a larger fall than the 3.0% in all other counties

Live births by year in the 578 counties that CDC WONDER identifies (counties with 100,000 or more residents in WONDER's population vintage) and in all other counties, which WONDER pools by state, 2018 to 2024, indexed to 2018 or as counts

measure	n	series	value	year
index	3,020,813	Named counties	100	2018
births	3,020,813	Named counties	3020813	2018
index	2,985,056	Named counties	98.82	2019
births	2,985,056	Named counties	2985056	2019
index	2,875,172	Named counties	95.18	2020
births	2,875,172	Named counties	2875172	2020
index	2,912,953	Named counties	96.43	2021
births	2,912,953	Named counties	2912953	2021
index	2,920,239	Named counties	96.67	2022
births	2,920,239	Named counties	2920239	2022
index	2,855,036	Named counties	94.51	2023
births	2,855,036	Named counties	2855036	2023
index	2,881,385	Named counties	95.38	2024
births	2,881,385	Named counties	2881385	2024
index	770,899	Other counties	100	2018
births	770,899	Other counties	770899	2018
index	762,484	Other counties	98.91	2019
births	762,484	Other counties	762484	2019
index	738,475	Other counties	95.79	2020
births	738,475	Other counties	738475	2020
index	751,339	Other counties	97.46	2021
births	751,339	Other counties	751339	2021
index	747,519	Other counties	96.97	2022
births	747,519	Other counties	747519	2022
index	740,981	Other counties	96.12	2023
births	740,981	Other counties	740981	2023
index	747,549	Other counties	96.97	2024
births	747,549	Other counties	747549	2024

Views: Index, 2018 = 100 (measure = index); Live births (measure = births).

Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.

Note: Births are full counts from birth certificates, so no interval is drawn. A count of births is not a birth rate: the series blends births per woman with the number of women.

Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error)

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_trend.json

Table 2. Of the 58 counties with the largest gains in births, 43 are in the South, which holds 40.1% of the named counties

Percent change in live births from 2018 to 2024 by county, for the 578 counties that CDC WONDER identifies (counties with 100,000 or more residents in WONDER's population vintage)

No inline rows: the values of Table 2 are in /data/where-births-are-falling/births_change_map.json.

Note: Births are full counts, so no interval is drawn for a county. A small county's count moves more from year to year by chance, so the shading of a county with few births is less stable than the shading of a large one.

Note: The tooltip gives the value of a county whose change is beyond the end of the key.

Note: Connecticut is shown as its eight legacy counties, the coding of the source. Alaska is drawn. Puerto Rico is not in these data and is not drawn.

Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error); county changes are not weighted

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_map.json

Table 3. The ten largest gains in births are all in the South, and the ten largest declines are spread across every Census region

Percent change in live births from 2018 to 2024 for the ten named counties with the largest gains and the ten with the largest declines, of the 578 named counties

births_2018	births_2024	change	county	group
1786	2993	67.58	Kaufman County, TX	Largest gains
1526	2203	44.36	Comal County, TX	Largest gains
2572	3670	42.69	Hays County, TX	Largest gains
6650	9325	40.23	Williamson County, TX	Largest gains
1537	2096	36.37	Parker County, TX	Largest gains
987	1320	33.74	Brunswick County, NC	Largest gains
2214	2914	31.62	Ellis County, TX	Largest gains
2299	2975	29.40	Johnston County, NC	Largest gains
1173	1501	27.96	Bartow County, GA	Largest gains
7355	9220	25.36	Montgomery County, TX	Largest gains
4127	3142	−23.87	St. Louis city, MO	Largest declines
3041	2361	−22.36	Hinds County, MS	Largest declines
1364	1062	−22.14	Humboldt County, CA	Largest declines
3109	2449	−21.23	St. Clair County, IL	Largest declines
1518	1204	−20.69	Monroe County, PA	Largest declines
1506	1195	−20.65	Terrebonne Parish, LA	Largest declines
8697	6930	−20.32	San Francisco County, CA	Largest declines
1326	1072	−19.16	Fayette County, PA	Largest declines
4656	3769	−19.05	Orleans Parish, LA	Largest declines
1246	1010	−18.94	Monroe County, IN	Largest declines

Note: Births are full counts, so no interval is drawn. The data table lists each county's births in 2018 and 2024.

Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error); county changes are not weighted

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_extremes.json

Table 4. Births in 2024 were below 2018 in all four quartiles of counties, by 5.6% in the least deprived and 7.3% in the most deprived, and in 2021 the other three quartiles rose by more than the most deprived

Pooled live births in each quartile of the 578 named counties by Area Deprivation Index rank, indexed to 2018 = 100, 2018 to 2024, with 95% intervals from a bootstrap over counties

conf_high	conf_low	index	n	quartile	year
n/a	n/a	100	1,224,834	Least deprived quartile	2018
99	98.12	98.51	1,206,641	Least deprived quartile	2019
95.57	93.10	94.28	1,154,721	Least deprived quartile	2020
97.84	93.85	95.77	1,173,023	Least deprived quartile	2021
97.77	93.60	95.59	1,170,851	Least deprived quartile	2022
95.57	90.73	93.09	1,140,185	Least deprived quartile	2023
97.19	91.77	94.43	1,156,626	Least deprived quartile	2024
n/a	n/a	100	710,664	Second quartile	2018
99.18	97.97	98.56	700,447	Second quartile	2019
96.58	94.40	95.43	678,194	Second quartile	2020
99.46	95.68	97.54	693,209	Second quartile	2021
100.9	95.90	98.47	699,762	Second quartile	2022
99.12	93.81	96.40	685,072	Second quartile	2023
100.6	94.70	97.44	692,445	Second quartile	2024
n/a	n/a	100	630,186	Third quartile	2018
99.75	98.96	99.31	625,862	Third quartile	2019
96.79	95.72	96.20	606,252	Third quartile	2020
98.35	96.20	97.14	612,146	Third quartile	2021
98.90	96.93	97.88	616,853	Third quartile	2022
97.59	95.05	96.34	607,127	Third quartile	2023
98.42	95.52	96.86	610,399	Third quartile	2024
n/a	n/a	100	455,129	Most deprived quartile	2018
99.76	98.90	99.34	452,106	Most deprived quartile	2019
96.26	95.35	95.80	436,005	Most deprived quartile	2020
96.17	94.80	95.48	434,575	Most deprived quartile	2021
96.14	93.99	95.09	432,773	Most deprived quartile	2022
94.09	91.59	92.86	422,652	Most deprived quartile	2023
94.20	91.23	92.70	421,915	Most deprived quartile	2024

Note: A tract's Area Deprivation Index national rank (1 is least deprived, 100 most) is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation. The index is a measure of neighborhoods, averaged to counties.

Source: CDC WONDER natality, births in 2018-2024; full counts of births; counties grouped by Area Deprivation Index 2023 with ACS 2019-2023 tract population (population-weighted); pooled over counties by births (births-weighted); intervals from a bootstrap over counties

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_by_deprivation.json

Table 5. The most deprived quartile of counties lost births in every Census region, and in the South the other three quartiles show no clear loss

Pooled change in live births from 2018 to 2024 by Census region and quartile of county deprivation rank, named counties, with 95% intervals from a bootstrap over counties

births_2018	change	conf_high	conf_low	n_lost_births	n_units	quartile	region
338526	−4.36	0.120	−7.66	24	39	Least deprived quartile	Northeast
76401	−1.99	−0.060	−3.67	16	25	Second quartile	Northeast
96145	−7.73	−4.41	−9.89	20	24	Third quartile	Northeast
48096	−9.26	−6.59	−11.84	21	22	Most deprived quartile	Northeast
52620	−5.68	n/a	n/a	6	9	Least deprived quartile	Midwest
158400	−10.63	−4.34	−14.08	19	26	Second quartile	Midwest
156974	−6.13	−4.79	−7.50	46	49	Third quartile	Midwest
189123	−9.20	−6.26	−11.60	44	53	Most deprived quartile	Midwest
183903	2.15	8.71	−4.06	17	35	Least deprived quartile	South
371925	1.30	4.59	−1.59	25	69	Second quartile	South
335404	0.340	3.71	−1.79	23	63	Third quartile	South
208110	−5.02	−2.92	−6.95	43	65	Most deprived quartile	South
649785	−8.37	−4.74	−11.55	46	61	Least deprived quartile	West
103938	−4.51	1.79	−7.96	17	25	Second quartile	West
41663	−9.28	n/a	n/a	8	8	Third quartile	West
9800	−9.27	n/a	n/a	5	5	Most deprived quartile	West

Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts. A cell with fewer than 10 counties shows no interval; in the West, the most deprived and third quartiles hold few counties, and the least deprived quartile of the Midwest holds fewer than 10, so those cells are thin.

Note: The Census South region is 16 states and DC; the Northeast, Midwest and West follow the Census Bureau's regions.

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_region_quartile.json

Table 6. Births fell for mothers aged 15 to 29, changed little for mothers aged 30 to 34 and rose for mothers aged 35 to 44 from 2018 to 2024

Pooled change in live births by mother's age band, 2018 to 2024, in the 578 named counties, with 95% intervals from a bootstrap over counties

age	births_2018	births_2024	change	conf_high	conf_low	n_units
15 to 19	129757	97772	−24.65	−22.72	−26.53	577
20 to 24	527582	439765	−16.65	−14.98	−18.31	578
25 to 29	848726	753795	−11.19	−9.57	−12.87	578
30 to 34	910977	920282	1.02	2.65	−0.620	578
35 to 39	490705	535630	9.16	11.05	7.32	578
40 to 44	103030	123085	19.47	22.34	17.02	578

Note: WONDER splits births into nine age bands. Mothers under 15 and mothers 45 and over are left out because WONDER withholds most of those cells; the methods note gives the counts. A withheld cell is missing, never zero, and a county that withholds a band in 2018 or 2024 is left out of that band's bar; the data table gives the number of counties in each bar.

Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; changes pooled over counties; intervals from a bootstrap over counties

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_by_mother_age.json

Table 7. In every quartile of county deprivation the share of births to older mothers rose and the share to younger mothers fell, and the differences between quartiles are larger than those changes

Share of births to mothers aged 15 to 24 and to mothers aged 35 to 44, among births to mothers aged 15 to 44, by quartile of county deprivation rank, 2018 and 2024, with 95% intervals from a bootstrap over counties

group_label	hi1	hi2	lo1	lo2	measure	n_units	y2018	y2024
All named counties	22.67	19.48	20.99	17.98	Mothers aged 15 to 24	578	21.83	18.73
Least deprived quartile	18.27	15.51	15.57	13.42	Mothers aged 15 to 24	144	16.96	14.46
Second quartile	22.09	18.75	20.07	16.95	Mothers aged 15 to 24	145	21.01	17.80
Third quartile	26.55	23.11	24.72	21.20	Mothers aged 15 to 24	144	25.63	22.18
Most deprived quartile	32.08	28.03	29.93	25.83	Mothers aged 15 to 24	145	30.94	26.91
All named counties	20.51	23.80	18.92	22.08	Mothers aged 35 to 44	578	19.72	22.95
Least deprived quartile	25.46	29.18	23.05	26.40	Mothers aged 35 to 44	144	24.32	27.84
Second quartile	20.45	23.86	18.51	21.75	Mothers aged 35 to 44	145	19.53	22.86
Third quartile	16.41	19.40	15.17	18.01	Mothers aged 35 to 44	144	15.87	18.76
Most deprived quartile	13.50	16.52	12.50	15.07	Mothers aged 35 to 44	145	13.01	15.79

Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts. Shares are of births to mothers aged 15 to 44; mothers under 15 and mothers 45 and over are left out, and withheld cells are missing.

Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; counties grouped by Area Deprivation Index 2023 with ACS 2019-2023 tract population (population-weighted); pooled over counties by births (births-weighted); intervals from a bootstrap over counties

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/mother_age_by_deprivation.json

Table 8. Counties with the largest declines in births lost births at every age under 35, and counties with the largest gains added births at every age from 25

Pooled change in live births from 2018 to 2024 by mother's age band, in four equal-sized groups of the 578 named counties formed by the change in their total births

age	age_position	change	group	n_units
15 to 19	1	−32.87	Largest declines	144
20 to 24	2	−25.09	Largest declines	144
25 to 29	3	−21.11	Largest declines	144
30 to 34	4	−8.77	Largest declines	144
35 to 39	5	−0.060	Largest declines	144
40 to 44	6	9.55	Largest declines	144
15 to 19	1	−25.21	Smaller declines	145
20 to 24	2	−17.85	Smaller declines	145
25 to 29	3	−13.39	Smaller declines	145
30 to 34	4	−0.670	Smaller declines	145
35 to 39	5	9.07	Smaller declines	145
40 to 44	6	20.34	Smaller declines	145
15 to 19	1	−20.90	Little change	144
20 to 24	2	−12.76	Little change	144
25 to 29	3	−7.43	Little change	144
30 to 34	4	4.50	Little change	144
35 to 39	5	13.88	Little change	144
40 to 44	6	23.02	Little change	144
15 to 19	1	−12.97	Largest gains	144
20 to 24	2	−4.05	Largest gains	145
25 to 29	3	5.80	Largest gains	145
30 to 34	4	19.11	Largest gains	145
35 to 39	5	24.75	Largest gains	145
40 to 44	6	39.26	Largest gains	145

Note: Counties are sorted into four groups of equal size by their percent change in total births from 2018 to 2024: the largest-decline group has falls of 8.8% or more, and the largest-gain group has gains of 2.6% or more. Births are full counts, so no interval is drawn; the groups are formed on the outcome, so an interval would not describe a draw of counties.

Note: A county that withholds a band in 2018 or 2024 is left out of that band's point.

Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; changes pooled over counties in each group

Data: vishalsingh.org/zipcode/report/where-births-are-falling/figures/age_change_by_county_change.json

All estimates

Every fact in facts.json (155), sorted by id. The same values as JSON: facts.json.

Fact id	Value	Unit	Estimand	Population	Period	Interval	n	Weights	Source
age_15	15	years of age	age below which WONDER's under-15 band applies; mothers under this age are left out (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
age_25	25	years of age	age from which births rise in the largest-gain counties (a definition of the band boundary used in the figure title)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
age_35	35	years of age	age below which a mother belongs to the younger groups in this chapter (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
age_45	45	years of age	age at which WONDER's 45-to-49 band begins; mothers of this age and older are left out (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_1519	15 to 19	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_1524	15 to 24	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_1529	15 to 29	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_1544	15 to 44	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_2024	20 to 24	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_2529	25 to 29	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_3034	30 to 34	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_3539	35 to 39	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_3544	35 to 44	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
band_4044	40 to 44	years of age	age-of-mother range used in this chapter, from WONDER's five-year bands (a definition)	mothers	all years (a definition)			none (definition)	CDC WONDER natality
births_named_2018	3.02 million	live births	count of live births	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018			none (full count)	CDC WONDER natality
births_named_2024	2.88 million	live births	count of live births	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2024			none (full count)	CDC WONDER natality
births_pooled_2018	0.77 million	live births	count of live births in the pooled rows	live births in the counties that WONDER natality does not name, which it pools within each state	2018			none (full count)	CDC WONDER natality
births_pooled_2024	0.75 million	live births	count of live births in the pooled rows	live births in the counties that WONDER natality does not name, which it pools within each state	2024			none (full count)	CDC WONDER natality
births_published_cells	20.4 million	live births	count of births in published cells	live births in the published age-of-mother cells of the named counties	births in 2018 to 2024		20,431,379 births	none (full count)	CDC WONDER natality
bottom_tenth_cut	13.6%	percent of 2018 births	fall at the 10th percentile of the county changes in births	named counties	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
bottom_tenth_n	58	counties	count of counties at or below the 10th percentile of change	named counties in the bottom tenth of change in births	births in 2018 and 2024			none (full count)	CDC WONDER natality
bottom_tenth_south	13	counties	count of those counties in the Census South region (16 states and DC)	named counties in the bottom tenth of change that are in the Census South region	births in 2018 and 2024			none (full count)	CDC WONDER natality
change_2021_q4	−0.3%	percent of 2020 births	pooled change in the count of births from 2020 to 2021, bootstrap interval over counties	live births in the most deprived quartile of the named counties by county Area Deprivation Index rank	2020 to 2021	95% CI −0.8% to 0.1%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
chg_3034	+1.0%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 30 to 34 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI −0.6% to 2.6%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
core_cells	24,276	cells	count of cells	county-year-by-age cells for mothers aged 15 to 44 in the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
core_withheld_cells	11	cells	count of cells with 1 to 9 births, which WONDER withholds	county-year-by-age cells for mothers aged 15 to 44 in the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
core_withheld_max_births	99	live births	largest number of births the withheld cells could hold: 9 births in each	withheld cells for mothers aged 15 to 44	births in 2018 to 2024			none (full count)	CDC WONDER natality
counties_declined	380	counties	count of counties with fewer births in 2024 than in 2018	named counties	births in 2018 and 2024			none (full count)	CDC WONDER natality
counties_rose	197	counties	count of counties with more births in 2024 than in 2018	named counties	births in 2018 and 2024			none (full count)	CDC WONDER natality
counties_unchanged	one	counties	count of counties with the same number of births in 2018 and 2024	named counties	births in 2018 and 2024			none (full count)	CDC WONDER natality
counties_used	578	counties	count of counties	counties that WONDER natality identifies in every year from 2018 to 2024 and that have births	births in 2018 to 2024			none (full count)	CDC WONDER natality
county_median_decline	3.8%	percent of 2018 births	median of the county changes in births, one county one count	the median named county	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
county_p5_decline	16.5%	percent of 2018 births	5th percentile of the county changes in births	named counties at the 5th percentile of change	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
county_p95_gain	19.9%	percent of 2018 births	95th percentile of the county changes in births	named counties at the 95th percentile of change	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
decline_2020	4.8%	percent of 2018 births	fall in the count of births from 2018 to 2020	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018 to 2020			none (full count)	CDC WONDER natality
decline_2023	5.5%	percent of 2018 births	fall in the count of births from 2018 to 2023	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018 to 2023			none (full count)	CDC WONDER natality
decline_mid	2.8%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the second and third quartiles together of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	95% CI 1.1% to 4.5%	289 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
decline_named	4.6%	percent of 2018 births	fall in the count of births from 2018 to 2024	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2018 to 2024			none (full count)	CDC WONDER natality
decline_pooled	3.0%	percent of 2018 births	fall in the count of births in the pooled rows from 2018 to 2024	live births in the counties that WONDER natality does not name, which it pools within each state	2018 to 2024			none (full count)	CDC WONDER natality
decline_q1	5.6%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the least deprived quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	95% CI 2.8% to 8.2%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
decline_q2	2.6%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the second quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	95% CI −0.6% to 5.3%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
decline_q3	3.1%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the third quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	95% CI 1.6% to 4.5%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
decline_q4	7.3%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the most deprived quartile of the named counties by county Area Deprivation Index rank	births in 2018 and 2024	95% CI 5.8% to 8.8%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
decline_us	4.3%	percent of 2018 births	fall in the count of births from 2018 to 2024	live births in the 50 states and DC	2018 to 2024			none (full count)	CDC WONDER natality
empty_shells	two	counties	count of listed counties whose births WONDER folded into the state's pooled row	county identifiers that WONDER lists in every year from 2018 to 2024 but with no births (Cape May County NJ, Portsmouth city VA)	births in 2018 to 2024			none (full count)	CDC WONDER natality
ext_min_births	987	live births	smallest 2018 count of births among those counties	the 20 counties in the figure of largest gains and declines	2018		20 counties	none (full count)	CDC WONDER natality
ext_n	ten	counties	number of counties listed in each group of largest gains and largest declines (a definition)	named counties	all years (a definition)			none (definition)	CDC WONDER natality
fall_1519	24.6%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 15 to 19 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI 22.7% to 26.5%	577 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_2024	16.6%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 20 to 24 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI 15.0% to 18.3%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_2529	11.2%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 25 to 29 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI 9.6% to 12.9%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_share_young	3.1 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24	births in 2018 and 2024	95% CI 2.9 percentage points to 3.3 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_young_diff	1.5 percentage points	percentage points	difference of two changes in pooled shares: fall in the share of births to mothers aged 15 to 24, most deprived quartile minus least deprived quartile, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually	births in 2018 and 2024	95% CI 0.9 percentage points to 2.2 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_young_q1	2.5 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; least deprived quartile	births in 2018 and 2024	95% CI 1.9 percentage points to 3.0 percentage points	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
fall_young_q4	4.0 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartile	births in 2018 and 2024	95% CI 3.7 percentage points to 4.4 percentage points	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
g1_chg_3539	−0.1%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 35 to 39 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g1_fall_1519	32.9%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 15 to 19 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g1_fall_2024	25.1%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 20 to 24 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g1_fall_2529	21.1%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 25 to 29 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g1_fall_3034	8.8%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 30 to 34 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g1_rise_4044	9.6%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 40 to 44 in the quarter of named counties with the largest declines that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g4_fall_1519	13.0%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 15 to 19 in the quarter of named counties with the largest gains that publish the band in both years	births in 2018 and 2024		144 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g4_fall_2024	4.0%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 20 to 24 in the quarter of named counties with the largest gains that publish the band in both years	births in 2018 and 2024		145 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g4_rise_2529	5.8%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 25 to 29 in the quarter of named counties with the largest gains that publish the band in both years	births in 2018 and 2024		145 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
g4_rise_4044	39.3%	percent of 2018 births	pooled change in the count of births from 2018 to 2024	live births to mothers aged 40 to 44 in the quarter of named counties with the largest gains that publish the band in both years	births in 2018 and 2024		145 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
gap_2021_q1	1.9 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, change from 2020 to 2021 in the least deprived quartile minus the change in the most deprived quartile	2020 to 2021	95% CI 1.0 percentage points to 3.0 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_2021_q2	2.5 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, change from 2020 to 2021 in the second quartile minus the change in the most deprived quartile	2020 to 2021	95% CI 1.4 percentage points to 3.6 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_2021_q3	1.3 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, change from 2020 to 2021 in the third quartile minus the change in the most deprived quartile	2020 to 2021	95% CI 0.5 percentage points to 2.2 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_older_2018	11.3 percentage points	percentage points	difference of two pooled shares of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartile minus most deprived quartile	2018	95% CI 10.0 percentage points to 12.5 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_older_2024	12.0 percentage points	percentage points	difference of two pooled shares of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartile minus most deprived quartile	2024	95% CI 10.5 percentage points to 13.5 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_young_2018	14.0 percentage points	percentage points	difference of two pooled shares of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartile minus least deprived quartile	2018	95% CI 12.3 percentage points to 15.8 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
gap_young_2024	12.4 percentage points	percentage points	difference of two pooled shares of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartile minus least deprived quartile	2024	95% CI 11.0 percentage points to 14.0 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
group_cut_decline	8.8%	percent of 2018 births	smallest fall among the counties in the largest-decline quarter (the group's own boundary member)	the quarter of named counties with the largest declines	births in 2018 and 2024		144 counties	none (full count)	CDC WONDER natality
group_cut_gain	2.6%	percent of 2018 births	smallest gain among the counties in the largest-gain quarter (the group's own boundary member)	the quarter of named counties with the largest gains	births in 2018 and 2024		145 counties	none (full count)	CDC WONDER natality
group_n_largest_declines	144	counties	count of counties	named counties in the quarter with the largest declines in births	births in 2018 and 2024			none (full count)	CDC WONDER natality
group_n_largest_gains	145	counties	count of counties	named counties in the quarter with the largest gains in births	births in 2018 and 2024			none (full count)	CDC WONDER natality
group_total_decline	13.5%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024	live births in the quarter of named counties with the largest declines	births in 2018 and 2024			births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
group_total_gain	11.2%	percent of 2018 births	rise in the pooled count of births from 2018 to 2024	live births in the quarter of named counties with the largest gains	births in 2018 and 2024			births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
largest_decline	23.9%	percent of 2018 births	fall in the county's count of births from 2018 to 2024	the named county with the largest decline (St. Louis city, MO)	births in 2018 and 2024		4,127 births	none (full count)	CDC WONDER natality
largest_gain	67.6%	percent of 2018 births	rise in the county's count of births from 2018 to 2024	the named county with the largest gain (Kaufman County, TX)	births in 2018 and 2024		1,786 births	none (full count)	CDC WONDER natality
map_beyond_key	34	counties	count of counties with a change of more than the key limit in either direction	named counties whose change is beyond the end of the map key	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
map_key_limit	20	percent of 2018 births	change in births at which the map key ends, in each direction (a display choice)	named counties on the map	births in 2018 and 2024			none (full count)	CDC WONDER natality
min_county_births	613	live births	smallest annual count of births in any of the named counties	the named county-year with the fewest births	births in 2018 to 2024		4,046 county-years	none (full count)	CDC WONDER natality
named_below_threshold	one	counties	count of named counties with a 2020 Census population below the threshold	named counties outside Connecticut whose 2020 Census population is below the threshold	2020 Census		3,135 counties	none (full count)	CDC WONDER natality
pctl_5	5th	percentile	percentile used to describe the spread of county changes (a definition)	named counties	all years (a definition)			none (definition)	CDC WONDER natality
pctl_95	95th	percentile	percentile used to describe the spread of county changes (a definition)	named counties	all years (a definition)			none (definition)	CDC WONDER natality
pooled_above_threshold	27	counties	count of unnamed counties with a 2020 Census population of at least the threshold	counties outside Connecticut that WONDER pools although their 2020 Census population is 100,000 or more	2020 Census		3,135 counties	none (full count)	CDC WONDER natality
pooled_rows	49	states	count of pooled rows	states with counties below the threshold, each with one pooled Unidentified Counties row	births in 2018 to 2024			none (full count)	CDC WONDER natality
q1_south_share	24%	percent of counties	share in the Census South region (16 states and DC)	counties in the least deprived quartile of the named counties	births in 2018 to 2024		144 counties	none (full count)	CDC WONDER natality
q1_vs_mid_pp	2.7 percentage points	percentage points	difference of two pooled falls in the count of births, shared bootstrap draws over counties	live births in the named counties, fall in births for the least deprived quartile minus the second and third quartiles together	births in 2018 and 2024	95% CI −0.5 percentage points to 5.9 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_midwest	9.2%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the most deprived quartile of the named counties in the Census Midwest region	births in 2018 and 2024	95% CI 6.3% to 11.6%	53 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_northeast	9.3%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the most deprived quartile of the named counties in the Census Northeast region	births in 2018 and 2024	95% CI 6.6% to 11.8%	22 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_south	5.0%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024, bootstrap interval over counties	live births in the most deprived quartile of the named counties in the Census South region	births in 2018 and 2024	95% CI 2.9% to 7.0%	65 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_south_share	45%	percent of counties	share in the Census South region (16 states and DC)	counties in the most deprived quartile of the named counties	births in 2018 to 2024		145 counties	none (full count)	CDC WONDER natality
q4_vs_mid_pp	4.5 percentage points	percentage points	difference of two pooled falls in the count of births, shared bootstrap draws over counties	live births in the named counties, fall in births for the most deprived quartile minus the second and third quartiles together	births in 2018 and 2024	95% CI 2.3 percentage points to 6.7 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_vs_q1_pp	1.7 percentage points	percentage points	difference of two pooled falls in the count of births, shared bootstrap draws over counties	live births in the named counties, fall in births for the most deprived quartile minus the least deprived quartile	births in 2018 and 2024	95% CI −1.2 percentage points to 5.0 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
q4_west	9.3%	percent of 2018 births	fall in the pooled count of births from 2018 to 2024; no interval, because the cell holds fewer than 10 counties (all of them lost births)	live births in the most deprived quartile of the named counties in the Census West region	births in 2018 and 2024		5 counties	births (a pooled ratio of totals over counties; full counts)	CDC WONDER natality
q4_west_n	5	counties	count of counties	counties in the most deprived quartile of the named counties in the Census West region	births in 2018 to 2024			none (full count)	CDC WONDER natality
region_midwest	−8.4%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census Midwest region	births in 2018 and 2024	95% CI −10.4% to −6.3%	137 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
region_northeast	−5.0%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census Northeast region	births in 2018 and 2024	95% CI −7.3% to −2.5%	110 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
region_south	0.0%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census South region	births in 2018 and 2024	95% CI −1.7% to 1.8%	232 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
region_west	−7.9%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the named counties in the Census West region	births in 2018 and 2024	95% CI −10.7% to −5.0%	99 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_2024	0.9%	percent of 2023 births	rise in the count of births from 2023 to 2024	live births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)	2023 to 2024			none (full count)	CDC WONDER natality
rise_3539	9.2%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 35 to 39 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI 7.3% to 11.0%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_4044	19.5%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births to mothers aged 40 to 44 in the named counties that publish the band in both years	births in 2018 and 2024	95% CI 17.0% to 22.3%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_older_diff	0.7 percentage points	percentage points	difference of two changes in pooled shares: rise in the share of births to mothers aged 35 to 44, least deprived quartile minus most deprived quartile, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually	births in 2018 and 2024	95% CI 0.3 percentage points to 1.2 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_older_q1	3.5 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartile	births in 2018 and 2024	95% CI 3.1 percentage points to 3.9 percentage points	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_older_q4	2.8 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; most deprived quartile	births in 2018 and 2024	95% CI 2.5 percentage points to 3.1 percentage points	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
rise_share_older	3.2 percentage points	percentage points	change from 2018 to 2024 in the pooled share of births, shared bootstrap draws over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44	births in 2018 and 2024	95% CI 3.1 percentage points to 3.4 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_declined	65.7%	percent of named counties	share of counties with fewer births in 2024 than in 2018	named counties	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
share_named_2018	79.7%	percent of live births in the United States	share of births in the named counties	live births in the 50 states and DC	2018			none (full count)	CDC WONDER natality
share_named_2024	79.4%	percent of live births in the United States	share of births in the named counties	live births in the 50 states and DC	2024			none (full count)	CDC WONDER natality
share_older_2018	19.7%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44	2018	95% CI 18.9% to 20.5%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_older_2024	22.9%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44	2024	95% CI 22.1% to 23.8%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_older_q1_2018	24.3%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 35 to 44	2018	95% CI 23.1% to 25.5%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_older_q1_2024	27.8%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 35 to 44	2024	95% CI 26.4% to 29.2%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_older_q4_2018	13.0%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 35 to 44	2018	95% CI 12.5% to 13.5%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_older_q4_2024	15.8%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 35 to 44	2024	95% CI 15.1% to 16.5%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_2018	21.8%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24	2018	95% CI 21.0% to 22.7%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_2024	18.7%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24	2024	95% CI 18.0% to 19.5%	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_q1_2018	17.0%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 15 to 24	2018	95% CI 15.6% to 18.3%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_q1_2024	14.5%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 15 to 24	2024	95% CI 13.4% to 15.5%	144 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_q4_2018	30.9%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 15 to 24	2018	95% CI 29.9% to 32.1%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
share_young_q4_2024	26.9%	percent of live births to mothers aged 15 to 44	pooled share of births in published cells, bootstrap interval over counties	live births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 15 to 24	2024	95% CI 25.8% to 28.0%	145 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
slope_u	−0.7 percentage points	percentage points of change in births per ten points of county deprivation rank	slope of the county change in births (percent) on county Area Deprivation Index rank, unweighted, one county one count, bootstrap interval over counties	named counties	births in 2018 and 2024	95% CI −1.1 percentage points to −0.3 percentage points	578 counties	none (each county counts once)	CDC WONDER natality
slope_w	+0.5 percentage points	percentage points of change in births per ten points of county deprivation rank	slope of the county change in births (percent) on county Area Deprivation Index rank, weighted by 2018 births, bootstrap interval over counties	named counties	births in 2018 and 2024	95% CI −0.2 percentage points to 1.2 percentage points	578 counties	2018 births	CDC WONDER natality
south_counties	232	counties	count of counties	named counties in the Census South region (16 states and DC)	births in 2018 to 2024			none (full count)	CDC WONDER natality
south_minus_midwest	8.4 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, South minus Midwest	births in 2018 and 2024	95% CI 5.7 percentage points to 11.1 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
south_minus_northeast	5.0 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, South minus Northeast	births in 2018 and 2024	95% CI 2.0 percentage points to 7.9 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
south_minus_west	7.9 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties, South minus West	births in 2018 and 2024	95% CI 4.3 percentage points to 11.3 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
south_q123	+1.1%	percent of 2018 births	pooled change in the count of births from 2018 to 2024, bootstrap interval over counties	live births in the three less deprived quartiles of the named counties in the Census South region	births in 2018 and 2024	95% CI −0.9% to 3.4%	167 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
south_q4_gap	6.1 percentage points	percentage points	difference of two pooled changes in the count of births, shared bootstrap draws over counties	live births in the named counties in the Census South region, three less deprived quartiles minus the most deprived	births in 2018 and 2024	95% CI 3.2 percentage points to 9.0 percentage points	578 counties	births in each county (a pooled ratio of sums over counties); interval from a bootstrap over counties	CDC WONDER natality
south_share	40.1%	percent of named counties	share of named counties in the Census South region (16 states and DC)	named counties	births in 2018 to 2024		578 counties	none (full count)	CDC WONDER natality
south_states	16	states	states in the Census South region, besides the District of Columbia (a definition)	states	all years (a definition)			none (definition)	CDC WONDER natality
ss_actual_p5	16.6%	percent of 2018 births	fall in the county's births to mothers aged 15 to 44, 5th percentile across counties	named counties at the 5th percentile of change in births to mothers aged 15 to 44	births in 2018 and 2024		577 counties	none (full count)	CDC WONDER natality
ss_actual_p95	19.8%	percent of 2018 births	gain in the county's births to mothers aged 15 to 44, 95th percentile across counties	named counties at the 95th percentile of change in births to mothers aged 15 to 44	births in 2018 and 2024		577 counties	none (full count)	CDC WONDER natality
ss_corr_u	−0.03	correlation coefficient	correlation, unweighted, one county one count, between the change in births that a county's 2018 age mix implies (each band changing at the all-county rate) and its change; county-cluster bootstrap interval	named counties that publish all six age bands in 2018 and 2024	births in 2018 and 2024	95% CI −0.11 to 0.04	577 counties	none (each county counts once)	CDC WONDER natality
ss_corr_w	−0.16	correlation coefficient	correlation, weighted by 2018 births to mothers aged 15 to 44, between the change in births that a county's 2018 age mix implies (each band changing at the all-county rate) and its change; county-cluster bootstrap interval	named counties that publish all six age bands in 2018 and 2024	births in 2018 and 2024	95% CI −0.26 to −0.06	577 counties	2018 births to mothers aged 15 to 44	CDC WONDER natality
ss_counties	577	counties	count of counties	named counties that publish all six age bands in 2018 and 2024	births in 2018 and 2024			none (full count)	CDC WONDER natality
ss_implied_p5	8.9%	percent of 2018 births	fall implied by the county's 2018 age mix, 5th percentile across counties	named counties at the 5th percentile of implied change	births in 2018 and 2024		577 counties	none (full count)	CDC WONDER natality
ss_implied_p95	1.3%	percent of 2018 births	fall implied by the county's 2018 age mix, 95th percentile across counties	named counties at the 95th percentile of implied change	births in 2018 and 2024		577 counties	none (full count)	CDC WONDER natality
ss_left_out	one	counties	count of counties left out of the shift-share check	named counties with a withheld age cell in 2018 or 2024	births in 2018 and 2024			none (full count)	CDC WONDER natality
tail_cells	12,138	cells	count of cells	county-year-by-age cells for mothers under 15 and 45 and over in the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
tail_published_share	0.26%	percent of live births	share of those births to mothers under 15 or 45 and over, in published cells	live births in the published age-of-mother cells of the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
tail_withheld_cells	6,594	cells	count of cells with 1 to 9 births, which WONDER withholds	county-year-by-age cells for mothers under 15 and 45 and over in the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
tail_withheld_max_share	0.29%	percent of live births	largest share of births the withheld tail cells could hold: 9 births in each, over births in published cells	live births in the published age-of-mother cells of the named counties	births in 2018 to 2024			none (full count)	CDC WONDER natality
thin_cell_limit	10	counties	fewest counties for which a bootstrap interval over counties is printed (the library's minimum number of clusters)	cells of the region-by-quartile figure	births in 2018 and 2024			none (full count)	CDC WONDER natality
top_tenth_cut	10.2%	percent of 2018 births	gain at the 90th percentile of the county changes in births	named counties	births in 2018 and 2024		578 counties	none (full count)	CDC WONDER natality
top_tenth_n	58	counties	count of counties at or above the 90th percentile of change	named counties in the top tenth of change in births	births in 2018 and 2024			none (full count)	CDC WONDER natality
top_tenth_other_max	5	counties	largest count of those counties in any state other than Texas and Florida	named counties in the top tenth of change, in the state with the next most	births in 2018 and 2024			none (full count)	CDC WONDER natality
top_tenth_south	43	counties	count of those counties in the Census South region (16 states and DC)	named counties in the top tenth of change that are in the Census South region	births in 2018 and 2024			none (full count)	CDC WONDER natality
top_tenth_texas	12	counties	count of those counties in Texas, which equals the count in Florida (asserted in the build)	named counties in the top tenth of change that are in Texas, a count that Florida also has	births in 2018 and 2024			none (full count)	CDC WONDER natality
us_births_2018	3.79 million	live births	count of live births	live births in the 50 states and DC	2018			none (full count)	CDC WONDER natality
us_births_2024	3.63 million	live births	count of live births	live births in the 50 states and DC	2024			none (full count)	CDC WONDER natality
wonder_suppression_floor	10	births	a cell with fewer births than this is withheld (a definition)	cells of the WONDER natality files	births in 2018 to 2024			none (definition)	CDC WONDER natality
wonder_threshold	100,000	residents	population size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)	counties that CDC WONDER natality identifies	births in 2018 to 2024			none (definition)	CDC WONDER natality

Definitions

Bootstrap interval: A range for an estimate found by recomputing it on many random resamples of the data and reading the range from the results. It shows how much the estimate would vary from sample to sample.
Area Deprivation Index (ADI): A score that ranks neighborhoods by income, education, employment and housing conditions drawn from the American Community Survey. In this book a higher national percentile means a more deprived neighborhood.
Population-weighted: Averaged so that each place counts in proportion to its number of residents, which lets a large county move the result more than a small one. An unweighted average counts every place equally.
Suppression: The withholding of a number because the count behind it is too small to publish without risking the identification of a person. A suppressed value is missing, not zero.
Ecological inference: Drawing conclusions about individuals from data about places or groups. A pattern across counties need not hold for the people inside them.

Methods

This chapter compares births from 2018 to 2024 across the 578 counties that CDC WONDER names individually in every year, a set chosen by population size in a vintage earlier than the 2020 Census and not by outcome, and across groups of those counties by deprivation quartile and region. The figures are counts and shares of births, not birth rates, because no file used here holds women by age for counties, and births by mother's age use six of nine bands because most cells of the youngest and oldest bands are withheld. Pooled changes weight each county by its births, and counties that WONDER pools into an Unidentified Counties row have no county value. Births are full counts, so the intervals show dependence on which counties are in a group and not sampling error.

Which births and counties are used

Births are counts from CDC WONDER natality for 2018 to 2024 (2024 is final), by county of the mother's residence. The 578 named counties are the counties that WONDER identifies in every year and that have births in every year: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. By 2020 Census population 27 counties outside Connecticut that have 100,000 or more residents are still pooled, and one named county is below it.

WONDER pools every other county in a state into one Unidentified Counties row (49 rows), which is used only for the comparison of the named counties with the rest of the country. WONDER lists two further identifiers in every year with no births (Cape May County NJ, Portsmouth city VA), which are left out. The panel is defined by size, not by outcome, and every named county appears in all seven years. County totals have no withheld cell.

Figures explained here: Figure 1 and Figure 2

How births by mother's age and withheld cells are handled

Births by mother's age come in nine bands. WONDER withholds cells of 1 to 9 births. A withheld cell is missing: it leaves the numerator and the denominator, which is the births in the published cells, and nothing is derived from a county total minus the published cells.

The six bands from 15 to 19 through 40 to 44 have 11 withheld cells of 24,276, which could hold at most 99 births. The under-15 band and the 45-and-over bands are left out because most of their cells are withheld (6,594 of 12,138); the published tail cells hold 0.26% of births and the withheld ones at most 0.29%.

A share is the births to mothers in an age range over births in the published cells for mothers aged 15 to 44, pooled over counties. A change in a band compares the counties that publish the band in both 2018 and 2024. No rate is computed: no file used here holds women by age for counties.

The shift-share check applies the all-county change of each age band to each county's 2018 age mix and correlates the implied change with the observed change in births to mothers aged 15 to 44.

Figures explained here: Figure 6, Figure 7 and Figure 8

How counties are ranked, grouped and weighted

A tract's Area Deprivation Index national rank is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population, with Connecticut tracts assigned to the eight legacy counties; quartiles hold equal numbers of the named counties. Regions are the four Census Bureau regions (the South has 16 states and DC).

Pooled changes, shares and differences are ratios of sums over counties, so they weight each county by its births.

The map draws every county of the book's county map; counties that WONDER does not name have no value.

Figures explained here: Figure 4, Figure 5 and Figure 2

What the intervals do and do not show

Births are full counts, so these intervals show dependence on which counties are in a group and not sampling error. A region-by-quartile cell with fewer than 10 counties shows no interval, because a bootstrap over so few counties is mechanical. The groups of counties formed by the change in total births are defined on the outcome and carry no interval.

How the bootstrap intervals are computed

Pooled changes, shares and differences carry 95% percentile intervals from a bootstrap that resamples whole counties (2,000 replicates, seed 12345), with the same draws for every statistic so that a difference has its own interval. Correlations and slopes use a county-cluster bootstrap.

What these data cannot show

References

Osterman, Michelle J. K.; Hamilton, Brady E.; Martin, Joyce A.; Driscoll, Anne K.; Valenzuela, Claudia P. (2026). Births: Final Data for 2024. National Vital Statistics Reports 75(2). doi:10.15620/cdc/252440
Kearney, Melissa S.; Levine, Phillip B.; Pardue, Luke (2022). The Puzzle of Falling US Birth Rates since the Great Recession. Journal of Economic Perspectives 36(1): 151-176. doi:10.1257/jep.36.1.151
Kind, Amy J. H.; Buckingham, William R. (2018). Making Neighborhood-Disadvantage Metrics Accessible: The Neighborhood Atlas. New England Journal of Medicine 378(26): 2456-2458. doi:10.1056/NEJMp1802313
Mathews, T. J.; Hamilton, Brady E. (2016). Mean Age of Mothers is on the Rise: United States, 2000-2014. NCHS Data Brief No. 232. www.cdc.gov/nchs/products/databriefs/db232.htm

Provenance

Pipeline version: 0.1.0
Build script: book2/chapters/where-births-are-falling/build.py (sha256 b47a334b398b4f7778e70d1b6a0a82dd6de30eed8a68b4e929b8ed5020155bf4)
Built on: 2026-10-09
Site commit: c2b1ff3309cb4a10833f884da91ac0057a66ad0a

Inputs

File	Size (bytes)	SHA-256, first 1 MB	SHA-256, last 1 MB
book2/chapters/where-births-are-falling/wbf_data.py	10,915	c22de29942e1370129073448041e75b29b65f809f2d479a637d32d40628460f8	c22de29942e1370129073448041e75b29b65f809f2d479a637d32d40628460f8
data/analytic/tract_atlas.parquet	39,659,925	29d5e4d943552d54aeb6ba92aadc939d9bd15bdea553c78357dbd516757be627	1e10d1ecf722340f23ee2212d4999a90250f85b65fa89b39e32db06d9472e22e
data/staged/births/wonder_natality_county_age_of_mother_2018_2024.parquet	99,054	b31e8b07c5eab8e54c94c4b57e7100327bf4dd6058d309cf128c3e4c640e44de	b31e8b07c5eab8e54c94c4b57e7100327bf4dd6058d309cf128c3e4c640e44de
data/staged/births/wonder_natality_county_total_2018_2024.parquet	41,774	e85d351fa72c022a05415d332185113b6badcaff1119da1d6f45c76ffe16d86d	e85d351fa72c022a05415d332185113b6badcaff1119da1d6f45c76ffe16d86d
data/staged/crosswalks/ct_tract2020_to_old_county.parquet	15,842	961ef39f31596ef65fca2c67d5f2f63e533c5dc9b49745d3bb6437844e4b831d	961ef39f31596ef65fca2c67d5f2f63e533c5dc9b49745d3bb6437844e4b831d

Outputs

File	SHA-256
facts.json	77dd7eeea51784d62bbc66c924c5860689674d3033447c7880a586600453d9d5
figures/age_change_by_county_change.json	826d10c0a72167e0dbc41166ca2774d1d5c1d8c76df276e0ba5c2e42c6a52c4e
figures/births_by_deprivation.json	a21507843ebed1ddc8e6328285a33c0c9239ee6232858f469a4f30a9ae0e438e
figures/births_by_mother_age.json	08b341775c96401ffd6ff6bf57bbe64d8290d998ed1ed855be2d5eea3e3d26a1
figures/births_change_extremes.json	b625f3ef03d0e5fe62215d49d4651873e4e901ed120902c74d870f7819eeb14a
figures/births_change_map.json	56281bbfe963990b15b8a6077266a4261a7dab56d91f830f4c6db01d66e89338
figures/births_change_region_quartile.json	056abf936ea3e1c4c3f5cfb66aeb3bf3434baee4c2b9d7cf2397c50dc584dd7b
figures/births_trend.json	245d4e7aa4082510358d578cd02c61ee0e58cc2ed2b5d567605029bc48714694
figures/mother_age_by_deprivation.json	a38297d682101f0ebc324d312b77f965d35e255e15d478ba0ea693591638de14
meta.json	78f25853ee414eae541cc5f9ab5f47a727040344922c9465602efd30b8f951ee
public/data/where-births-are-falling/births_change_map.json	9751a5d7cca25f7381cc4799d7262211ddee3ea0e1182d31d8f3646e39d6238b
refs.json	8ce76203656a29a39f6fa686e3886d08269b60425bc06bce02adb1cedd12496b

Machine formats

Report (Markdown): https://vishalsingh.org/zipcode/where-births-are-falling/report.md
Every estimate (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/facts.json
Table 1, figure "births_trend" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_trend.json
Table 2, figure "births_change_map" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_map.json
Table 3, figure "births_change_extremes" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_extremes.json
Table 4, figure "births_by_deprivation" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_by_deprivation.json
Table 5, figure "births_change_region_quartile" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_change_region_quartile.json
Table 6, figure "births_by_mother_age" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/births_by_mother_age.json
Table 7, figure "mother_age_by_deprivation" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/mother_age_by_deprivation.json
Table 8, figure "age_change_by_county_change" (JSON): https://vishalsingh.org/zipcode/report/where-births-are-falling/figures/age_change_by_county_change.json
Payload of "births_change_map" (JSON): https://vishalsingh.org/zipcode/data/where-births-are-falling/births_change_map.json
Index of every report: https://vishalsingh.org/zipcode/llms.txt; all reports in one file: https://vishalsingh.org/zipcode/llms-full.txt

Identification

Principal estimates

Findings

Births have not returned to their 2018 level

Births held up in the South and fell elsewhere

The most deprived counties lost more births than the middle quartiles

A larger share of births were to older mothers in 2024

The age mix differs more across counties than it changed

Counties that lost the most births lost them among younger mothers

What these data cannot show

Tables

Table 1. Births in the named counties fell 4.6% from 2018 to 2024 with a low in 2023, a larger fall than the 3.0% in all other counties

Table 2. Of the 58 counties with the largest gains in births, 43 are in the South, which holds 40.1% of the named counties

Table 3. The ten largest gains in births are all in the South, and the ten largest declines are spread across every Census region

Table 4. Births in 2024 were below 2018 in all four quartiles of counties, by 5.6% in the least deprived and 7.3% in the most deprived, and in 2021 the other three quartiles rose by more than the most deprived

Table 5. The most deprived quartile of counties lost births in every Census region, and in the South the other three quartiles show no clear loss

Table 6. Births fell for mothers aged 15 to 29, changed little for mothers aged 30 to 34 and rose for mothers aged 35 to 44 from 2018 to 2024

Table 7. In every quartile of county deprivation the share of births to older mothers rose and the share to younger mothers fell, and the differences between quartiles are larger than those changes

Table 8. Counties with the largest declines in births lost births at every age under 35, and counties with the largest gains added births at every age from 25

All estimates

Definitions

Methods

Which births and counties are used

How births by mother's age and withheld cells are handled

How counties are ranked, grouped and weighted

What the intervals do and do not show

How the bootstrap intervals are computed

What these data cannot show

References

Provenance

Machine formats