{
  "alt": "Dot plot with one row per presidential election from 2008 to 2024, giving the CES Democratic share minus the certified national share with a confidence interval and a line at zero. Every difference is within {fact:bench_max} points of zero. The largest is in 2012, where the interval does not include zero, and the intervals for the other four elections include zero.",
  "caption": "The largest difference is {fact:bench_max} points, in 2012, where the survey is above the count and the count lies outside the survey interval; in the other four elections the count lies inside it. Each dot is the CES Democratic share minus the certified national two-party share, with the survey's confidence interval. The CES share covers all two-party voters, whether or not they reported income.",
  "data": [
    {
      "certified": 53.7708,
      "ces": 53.8895,
      "conf_high": 0.889818,
      "conf_low": -0.652299,
      "difference": 0.11876,
      "election": "2008",
      "n": 23585
    },
    {
      "certified": 52.0099,
      "ces": 53.0691,
      "conf_high": 1.8158,
      "conf_low": 0.302556,
      "difference": 1.05918,
      "election": "2012",
      "n": 37789
    },
    {
      "certified": 51.1625,
      "ces": 50.9933,
      "conf_high": 0.486654,
      "conf_low": -0.824972,
      "difference": -0.169159,
      "election": "2016",
      "n": 40891
    },
    {
      "certified": 52.268,
      "ces": 52.5253,
      "conf_high": 0.874758,
      "conf_low": -0.360204,
      "difference": 0.257277,
      "election": "2020",
      "n": 43872
    },
    {
      "certified": 49.2499,
      "ces": 48.9597,
      "conf_high": 0.465027,
      "conf_low": -1.04551,
      "difference": -0.290239,
      "election": "2024",
      "n": 42008
    }
  ],
  "id": "survey_vs_certified",
  "notes": [
    "The certified share is a full count and has no sampling interval; the interval shown is the survey's."
  ],
  "source": "Cooperative Election Study cumulative file, 2008-2024; weighted (weight_cumulative). MIT Election Data and Science Lab state presidential returns, 1976-2024; full counts (unweighted)",
  "spec": {
    "hi": "conf_high",
    "lo": "conf_low",
    "n": "n",
    "reference": 0,
    "referenceLabel": "No difference",
    "sort": "data",
    "x": "difference",
    "xDomain": [
      -2,
      2
    ],
    "xFormat": {
      "digits": 1,
      "signed": true
    },
    "xLabel": "CES minus certified count, Democratic share (percentage points)",
    "y": "election"
  },
  "subtitle": "Democratic share of the two-party presidential vote, CES respondents minus the certified national count, percentage points, by election; two-party voters whether or not they reported income; 95% intervals from the Kish effective sample size",
  "table": {
    "columns": [
      {
        "key": "election",
        "label": "Election"
      },
      {
        "format": {
          "digits": 1
        },
        "key": "ces",
        "label": "CES (%)"
      },
      {
        "format": {
          "digits": 1
        },
        "key": "certified",
        "label": "Certified (%)"
      },
      {
        "format": {
          "digits": 1,
          "signed": true
        },
        "key": "difference",
        "label": "Difference (points)"
      },
      {
        "format": {
          "digits": 1,
          "signed": true
        },
        "key": "conf_low",
        "label": "95% CI low"
      },
      {
        "format": {
          "digits": 1,
          "signed": true
        },
        "key": "conf_high",
        "label": "95% CI high"
      },
      {
        "key": "n",
        "label": "n voters"
      }
    ]
  },
  "title": "In every election the survey's Democratic share is within {fact:bench_max} points of the certified national result",
  "type": "dot",
  "width": "body"
}