Elections Performance Index

The Elections Performance Index was transferred to the MIT Election Data & Science Lab on Aug. 9, 2018. Please visit http://elections.mit.edu for information on the 2016 election and future updates.

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  • Election Overview

    See how states performed in the past four national elections.

  • EPI Rank

    Examine each state’s Elections Performance Index averages by election year.

  • State Profiles

    Explore each state to see how its performance has changed overall and by indicator.

  • Indicators

    Take an in-depth look at each indicator used to calculate the Elections Performance Index.

  • Comparison Tool

    Compare states and regions to the national average by election for each indicator.

The Elections Performance Index, or EPI, is the first comprehensive assessment of election administration in all 50 states and the District of Columbia.

Using data from 17 key indicators, the EPI makes it possible to compare election administration policy and performance across the states and from one election cycle to the next.

The index presented here is based on the 2008, 2010, 2012, and 2014 elections.

Election Overview

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  • improved
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  • worsened
Select a state to view its EPI performance

Select a state to the left to explore its overall EPI average and performance on individual indicators in 2008, 2010, 2012, and 2014. Within each state page, users also have the opportunity to compare across elections by type to see changes by indicator among the midterms: 2010 and 2014; and the presidentials: 2008 and 2012.

  • %

    Overall EPI Average2012 Rank #1

  • % +1%

    Provisional Ballots Rejected

  • % +1%

    Absentee Ballots Unreturned

  • % +1%

    Lookup Tools

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Nationwide average
Worsened No change Improved
Best Worst
Trouble Printing dialog.

Select individual states or a predefined group to compare

Compare the performance of individual states, regions, and groups of states on each indicator during each election year. Select the "compare elections" option to see how states' indicator values changed between the 2010 and 2014 midterms and the 2008 and 2012 presidential elections.

Note: This content scrolls horizontally on small screens.

Change 20102014

Nationwide average
Best Worst
Select an indicator to view its profile

Learn more about the indicators used to calculate the Elections Performance Index by selecting them on the left. See how performance on each indicator changes across election years.

Best Worst

Using data from the U.S. Election Assistance Commission’s Election Administration and Voting Survey, this indicator measures the percentage—out of all ballots cast—of absentee ballots that were rejected.

In 1988, only six states allowed individuals to cast an absentee ballot by mail without an excuse. By the 2008 election, that number had grown to 27.

Absentee balloting allows voters to cast a ballot at their convenience without having to go to the polls on Election Day, while also spreading election officials’ workload over a longer voting period.

Unlike in-person voters, however, who may have an opportunity to correct errors, absentee voters have no recourse to fix a ballot if a mistake is made. If there is an errant mark and a machine cannot read the ballot, there is a greater chance that the ballot will not be counted.

States have adopted absentee balloting in different ways:

  • Limited Absentee States require a registered voter to provide a reason when requesting an absentee ballot (e.g., illness, disability, travel, etc.). Such states typically have lower rates of absentee ballots rejected compared with No-excuse Absentee States.
  • No-excuse Absentee States allow any registered voter to request an absentee ballot without providing a reason. Such states typically have higher rates of absentee ballots rejected than do Limited Absentee States.
  • Permanent Absentee States are a subset of No-excuse Absentee States that also give any registered voter the option to receive automatically mailed absentee ballots for future elections. Such states tend to have higher rejected absentee ballots than do other states.
  • Vote-by-Mail States conduct elections entirely by mail.
Assessing the 2014 Election
Assessing the 2014 Election
Issue Brief

Assessing the 2014 Election

The Elections Performance Index has been updated to include data from 2014.

Quick View
Issue Brief

In 2013, The Pew Charitable Trusts unveiled the Elections Performance Index (EPI), which provided the first comprehensive assessment of election administration in all 50 states and the District of Columbia. The interactive tool introduced the index’s performance indicators, summarized 2008 and 2010 data, and ranked the states according to their overall EPI averages, or scores, which give users a way to evaluate states’ election performance side by side and over time.