{
  "alt": "Line chart of three vote-weighted standard deviations of two-party margin, 1868 to 2024. The spread of state margins around the national margin is {fact:sd_between_1904} points in 1904, {fact:sd_between_1924} in 1924, {fact:sd_between_1976} in 1976 and {fact:sd_between_2024} in 2024. The spread of county margins around their own state's margin is {fact:sd_within_1976} in 1976, {fact:sd_within_2016} in 2016 and {fact:sd_within_2024} in 2024. The spread of county margins around the nation is {fact:sd_all_1976} in 1976 and {fact:sd_all_2024} in 2024.",
  "caption": "Between states, the spread of state margins around the national margin, peaks in 1924 at {fact:sd_between_1924} points, rises from {fact:sd_between_1976} points in 1976 to {fact:sd_between_2024} in 2024, and in 2024 lies {fact:sd_between_gap} points below its lowest value from 1892 to 1924, {fact:sd_between_min}. Within states, the spread of county margins around their own state's margin, peaks in 2016 at {fact:sd_within_2016} points, and its 2024 value lies {fact:sd_within_gap} points above the highest value before 2000, {fact:sd_within_prior_max} in 1872. All counties, the spread of county margins around the national margin, needs no cutoff: {fact:sd_all_1976} points in 1976 and {fact:sd_all_2024} in 2024. Its square is the sum of the squares of the other two lines. Shaded columns mark third-party years, listed in the text.",
  "data": [
    {
      "flag": "",
      "n_units": 1696,
      "series": "All counties",
      "spread": 30.5979,
      "year": 1868
    },
    {
      "flag": "",
      "n_units": 33,
      "series": "Between states",
      "spread": 18.258,
      "year": 1868
    },
    {
      "flag": "",
      "n_units": 1696,
      "series": "Within states",
      "spread": 24.5535,
      "year": 1868
    },
    {
      "flag": "",
      "n_units": 2160,
      "series": "All counties",
      "spread": 34.4225,
      "year": 1872
    },
    {
      "flag": "",
      "n_units": 37,
      "series": "Between states",
      "spread": 21.0835,
      "year": 1872
    },
    {
      "flag": "",
      "n_units": 2160,
      "series": "Within states",
      "spread": 27.2102,
      "year": 1872
    },
    {
      "flag": "",
      "n_units": 2230,
      "series": "All counties",
      "spread": 26.818,
      "year": 1876
    },
    {
      "flag": "",
      "n_units": 37,
      "series": "Between states",
      "spread": 15.1908,
      "year": 1876
    },
    {
      "flag": "",
      "n_units": 2230,
      "series": "Within states",
      "spread": 22.1007,
      "year": 1876
    },
    {
      "flag": "",
      "n_units": 2291,
      "series": "All counties",
      "spread": 26.7782,
      "year": 1880
    },
    {
      "flag": "",
      "n_units": 38,
      "series": "Between states",
      "spread": 16.5252,
      "year": 1880
    },
    {
      "flag": "",
      "n_units": 2291,
      "series": "Within states",
      "spread": 21.071,
      "year": 1880
    },
    {
      "flag": "",
      "n_units": 2351,
      "series": "All counties",
      "spread": 24.3049,
      "year": 1884
    },
    {
      "flag": "",
      "n_units": 38,
      "series": "Between states",
      "spread": 14.1172,
      "year": 1884
    },
    {
      "flag": "",
      "n_units": 2351,
      "series": "Within states",
      "spread": 19.7846,
      "year": 1884
    },
    {
      "flag": "",
      "n_units": 2429,
      "series": "All counties",
      "spread": 24.5124,
      "year": 1888
    },
    {
      "flag": "",
      "n_units": 38,
      "series": "Between states",
      "spread": 15.9013,
      "year": 1888
    },
    {
      "flag": "",
      "n_units": 2429,
      "series": "Within states",
      "spread": 18.6549,
      "year": 1888
    },
    {
      "flag": "Third-party year",
      "n_units": 2658,
      "series": "All counties",
      "spread": 30.9165,
      "year": 1892
    },
    {
      "flag": "Third-party year",
      "n_units": 44,
      "series": "Between states",
      "spread": 25.5395,
      "year": 1892
    },
    {
      "flag": "Third-party year",
      "n_units": 2658,
      "series": "Within states",
      "spread": 17.4232,
      "year": 1892
    },
    {
      "flag": "",
      "n_units": 2715,
      "series": "All counties",
      "spread": 32.9983,
      "year": 1896
    },
    {
      "flag": "",
      "n_units": 45,
      "series": "Between states",
      "spread": 27.5802,
      "year": 1896
    },
    {
      "flag": "",
      "n_units": 2715,
      "series": "Within states",
      "spread": 18.1167,
      "year": 1896
    },
    {
      "flag": "",
      "n_units": 2711,
      "series": "All counties",
      "spread": 25.3257,
      "year": 1900
    },
    {
      "flag": "",
      "n_units": 45,
      "series": "Between states",
      "spread": 17.922,
      "year": 1900
    },
    {
      "flag": "",
      "n_units": 2711,
      "series": "Within states",
      "spread": 17.8939,
      "year": 1900
    },
    {
      "flag": "",
      "n_units": 2723,
      "series": "All counties",
      "spread": 32.4027,
      "year": 1904
    },
    {
      "flag": "",
      "n_units": 45,
      "series": "Between states",
      "spread": 26.3515,
      "year": 1904
    },
    {
      "flag": "",
      "n_units": 2723,
      "series": "Within states",
      "spread": 18.8555,
      "year": 1904
    },
    {
      "flag": "",
      "n_units": 2856,
      "series": "All counties",
      "spread": 26.1087,
      "year": 1908
    },
    {
      "flag": "",
      "n_units": 46,
      "series": "Between states",
      "spread": 19.9994,
      "year": 1908
    },
    {
      "flag": "",
      "n_units": 2856,
      "series": "Within states",
      "spread": 16.7836,
      "year": 1908
    },
    {
      "flag": "Third-party year",
      "n_units": 2943,
      "series": "All counties",
      "spread": 30.65,
      "year": 1912
    },
    {
      "flag": "Third-party year",
      "n_units": 47,
      "series": "Between states",
      "spread": 23.482,
      "year": 1912
    },
    {
      "flag": "Third-party year",
      "n_units": 2943,
      "series": "Within states",
      "spread": 19.6981,
      "year": 1912
    },
    {
      "flag": "",
      "n_units": 3022,
      "series": "All counties",
      "spread": 25.3065,
      "year": 1916
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 19.5772,
      "year": 1916
    },
    {
      "flag": "",
      "n_units": 3022,
      "series": "Within states",
      "spread": 16.036,
      "year": 1916
    },
    {
      "flag": "",
      "n_units": 3054,
      "series": "All counties",
      "spread": 29.8178,
      "year": 1920
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 24.6847,
      "year": 1920
    },
    {
      "flag": "",
      "n_units": 3054,
      "series": "Within states",
      "spread": 16.7262,
      "year": 1920
    },
    {
      "flag": "Third-party year",
      "n_units": 3083,
      "series": "All counties",
      "spread": 36.9504,
      "year": 1924
    },
    {
      "flag": "Third-party year",
      "n_units": 48,
      "series": "Between states",
      "spread": 31.8246,
      "year": 1924
    },
    {
      "flag": "Third-party year",
      "n_units": 3083,
      "series": "Within states",
      "spread": 18.7757,
      "year": 1924
    },
    {
      "flag": "",
      "n_units": 3097,
      "series": "All counties",
      "spread": 25.5527,
      "year": 1928
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 15.9218,
      "year": 1928
    },
    {
      "flag": "",
      "n_units": 3097,
      "series": "Within states",
      "spread": 19.986,
      "year": 1928
    },
    {
      "flag": "",
      "n_units": 3096,
      "series": "All counties",
      "spread": 26.3716,
      "year": 1932
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 19.5244,
      "year": 1932
    },
    {
      "flag": "",
      "n_units": 3096,
      "series": "Within states",
      "spread": 17.7272,
      "year": 1932
    },
    {
      "flag": "",
      "n_units": 3095,
      "series": "All counties",
      "spread": 24.8935,
      "year": 1936
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 15.6501,
      "year": 1936
    },
    {
      "flag": "",
      "n_units": 3095,
      "series": "Within states",
      "spread": 19.3587,
      "year": 1936
    },
    {
      "flag": "",
      "n_units": 3094,
      "series": "All counties",
      "spread": 25.7895,
      "year": 1940
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 18.1762,
      "year": 1940
    },
    {
      "flag": "",
      "n_units": 3094,
      "series": "Within states",
      "spread": 18.2954,
      "year": 1940
    },
    {
      "flag": "",
      "n_units": 3095,
      "series": "All counties",
      "spread": 25.1245,
      "year": 1944
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 16.7742,
      "year": 1944
    },
    {
      "flag": "",
      "n_units": 3095,
      "series": "Within states",
      "spread": 18.7047,
      "year": 1944
    },
    {
      "flag": "Third-party year",
      "n_units": 3096,
      "series": "All counties",
      "spread": 22.6299,
      "year": 1948
    },
    {
      "flag": "Third-party year",
      "n_units": 48,
      "series": "Between states",
      "spread": 12.9404,
      "year": 1948
    },
    {
      "flag": "Third-party year",
      "n_units": 3096,
      "series": "Within states",
      "spread": 18.565,
      "year": 1948
    },
    {
      "flag": "",
      "n_units": 3098,
      "series": "All counties",
      "spread": 22.5236,
      "year": 1952
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 12.6017,
      "year": 1952
    },
    {
      "flag": "",
      "n_units": 3098,
      "series": "Within states",
      "spread": 18.6685,
      "year": 1952
    },
    {
      "flag": "",
      "n_units": 3100,
      "series": "All counties",
      "spread": 21.3737,
      "year": 1956
    },
    {
      "flag": "",
      "n_units": 48,
      "series": "Between states",
      "spread": 10.8812,
      "year": 1956
    },
    {
      "flag": "",
      "n_units": 3100,
      "series": "Within states",
      "spread": 18.3966,
      "year": 1956
    },
    {
      "flag": "",
      "n_units": 3105,
      "series": "All counties",
      "spread": 20.9367,
      "year": 1960
    },
    {
      "flag": "",
      "n_units": 49,
      "series": "Between states",
      "spread": 8.83817,
      "year": 1960
    },
    {
      "flag": "",
      "n_units": 3105,
      "series": "Within states",
      "spread": 18.9798,
      "year": 1960
    },
    {
      "flag": "",
      "n_units": 3107,
      "series": "All counties",
      "spread": 22.1994,
      "year": 1964
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 16.4439,
      "year": 1964
    },
    {
      "flag": "",
      "n_units": 3107,
      "series": "Within states",
      "spread": 14.9134,
      "year": 1964
    },
    {
      "flag": "Third-party year",
      "n_units": 3111,
      "series": "All counties",
      "spread": 23.279,
      "year": 1968
    },
    {
      "flag": "Third-party year",
      "n_units": 50,
      "series": "Between states",
      "spread": 13.6467,
      "year": 1968
    },
    {
      "flag": "Third-party year",
      "n_units": 3111,
      "series": "Within states",
      "spread": 18.8595,
      "year": 1968
    },
    {
      "flag": "",
      "n_units": 3110,
      "series": "All counties",
      "spread": 20.4505,
      "year": 1972
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 13.3809,
      "year": 1972
    },
    {
      "flag": "",
      "n_units": 3110,
      "series": "Within states",
      "spread": 15.4653,
      "year": 1972
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "All counties",
      "spread": 18.3622,
      "year": 1976
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 9.44424,
      "year": 1976
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "Within states",
      "spread": 15.7472,
      "year": 1976
    },
    {
      "flag": "",
      "n_units": 3112,
      "series": "All counties",
      "spread": 20.9124,
      "year": 1980
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 11.4139,
      "year": 1980
    },
    {
      "flag": "",
      "n_units": 3112,
      "series": "Within states",
      "spread": 17.5228,
      "year": 1980
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 21.6861,
      "year": 1984
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 10.3724,
      "year": 1984
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 19.0446,
      "year": 1984
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 21.3344,
      "year": 1988
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 10.2929,
      "year": 1988
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 18.6872,
      "year": 1988
    },
    {
      "flag": "Third-party year",
      "n_units": 3115,
      "series": "All counties",
      "spread": 22.0841,
      "year": 1992
    },
    {
      "flag": "Third-party year",
      "n_units": 50,
      "series": "Between states",
      "spread": 10.9173,
      "year": 1992
    },
    {
      "flag": "Third-party year",
      "n_units": 3115,
      "series": "Within states",
      "spread": 19.1969,
      "year": 1992
    },
    {
      "flag": "Third-party year",
      "n_units": 3114,
      "series": "All counties",
      "spread": 23.5766,
      "year": 1996
    },
    {
      "flag": "Third-party year",
      "n_units": 50,
      "series": "Between states",
      "spread": 13.1229,
      "year": 1996
    },
    {
      "flag": "Third-party year",
      "n_units": 3114,
      "series": "Within states",
      "spread": 19.5869,
      "year": 1996
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 26.5236,
      "year": 2000
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 15.5009,
      "year": 2000
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 21.5226,
      "year": 2000
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 27.3459,
      "year": 2004
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 14.8625,
      "year": 2004
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 22.9544,
      "year": 2004
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 28.7629,
      "year": 2008
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 16.1756,
      "year": 2008
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 23.7835,
      "year": 2008
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "All counties",
      "spread": 31.0706,
      "year": 2012
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 17.3922,
      "year": 2012
    },
    {
      "flag": "",
      "n_units": 3114,
      "series": "Within states",
      "spread": 25.7467,
      "year": 2012
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "All counties",
      "spread": 35.8973,
      "year": 2016
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 19.2859,
      "year": 2016
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "Within states",
      "spread": 30.2765,
      "year": 2016
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "All counties",
      "spread": 33.951,
      "year": 2020
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 18.2872,
      "year": 2020
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "Within states",
      "spread": 28.605,
      "year": 2020
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "All counties",
      "spread": 32.7457,
      "year": 2024
    },
    {
      "flag": "",
      "n_units": 50,
      "series": "Between states",
      "spread": 17.194,
      "year": 2024
    },
    {
      "flag": "",
      "n_units": 3113,
      "series": "Within states",
      "spread": 27.8684,
      "year": 2024
    }
  ],
  "id": "states_and_counties",
  "notes": [
    "States are the states and the District of Columbia with returns in the election; a state's margin is its summed two-party margin. The number of states is {fact:n_states_1868} in 1868, when four Confederate states have no returns, and {fact:n_states_1976} in both 1976 and 2024, so the between-state series compares the same units in those two elections. The within-state series is measured on counties. The 1872 values rest on Reconstruction-era returns."
  ],
  "source": "County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; shares weighted by two-party votes unless stated",
  "spec": {
    "annotations": [
      {
        "type": "band",
        "x1": 1891,
        "x2": 1893
      },
      {
        "type": "band",
        "x1": 1911,
        "x2": 1913
      },
      {
        "type": "band",
        "x1": 1923,
        "x2": 1925
      },
      {
        "type": "band",
        "x1": 1947,
        "x2": 1949
      },
      {
        "type": "band",
        "x1": 1967,
        "x2": 1969
      },
      {
        "type": "band",
        "x1": 1991,
        "x2": 1993
      },
      {
        "type": "band",
        "x1": 1995,
        "x2": 1997
      }
    ],
    "colors": {
      "All counties": "total",
      "Between states": "cat6",
      "Within states": "cat7"
    },
    "dashed": [
      "Within states"
    ],
    "endLabels": true,
    "n": "n_units",
    "series": "series",
    "x": "year",
    "xDomain": [
      1868,
      2024
    ],
    "xFormat": {
      "digits": 0
    },
    "xLabel": "Presidential election year",
    "y": "spread",
    "yDomain": [
      0,
      40
    ],
    "yFormat": {
      "digits": 0
    },
    "yLabel": "Vote-weighted standard deviation of margins (points)"
  },
  "subtitle": "Vote-weighted standard deviation of two-party margins, percentage points: county margins around the national margin, state margins around the national margin, and county margins around their own state's margin, 1868 to 2024",
  "table": {
    "columns": [
      {
        "key": "series",
        "label": "Measure"
      },
      {
        "format": {
          "digits": 0
        },
        "key": "year",
        "label": "Election"
      },
      {
        "format": {
          "digits": 1
        },
        "key": "spread",
        "label": "Standard deviation (points)"
      },
      {
        "format": {
          "digits": 0,
          "thousands": true
        },
        "key": "n_units",
        "label": "Units"
      },
      {
        "key": "flag",
        "label": "Note"
      }
    ]
  },
  "title": "The spread of state margins around the national margin rose from {fact:sd_between_1976} points in 1976 to {fact:sd_between_2024} in 2024",
  "type": "line",
  "width": "wide"
}