Electoral Environment Changes Since 2008
Diving deeper into the voter registration rate and voter turnout indicators.
The Elections Performance Index (EPI) tracks election administration and management outcomes going back to 2008, working to produce an accurate portrayal of how elections work for practitioners, academics, and voters. There are 19 different indicators in the EPI, all of which work together to illustrate how election management in the U.S. has changed over time. Election administration is not static, with changes coming from unpredictable events like the COVID-19 pandemic, technological advances, new best practices, and shifts in the political landscape that all impact the administering of elections at the local, state, and national levels.
The voter registration rate and voter turnout rate are perhaps two of the most well-known metrics that we use in the EPI. Together, these two indicators convey information about the electoral environment in all 50 states and Washington D.C—specifically on two touchpoints where voters can engage directly with election officials, and where the outcomes of election policies can be the most publicly visible.
There is a nuanced relationship between election officials, the policies they’re tasked with administering, public perception, and actual voter outcomes. It is often outside of the direct purview of election officials to set the big-picture policies which govern voter outcomes. Yet at the same time, the success of voter registration and turnout programs affects public perception surrounding the health of our election systems nationwide.
Regardless of the intricacies surrounding the systems that the voter registration and voter turnout indicators operate within, they remain two vitally important metrics in the EPI. Especially in the case of voter registration, more needs to be done to support academics and election officials in understanding and making improvements to voter registration and list maintenance processes. (We recently launched a new grant program to do just that; you can learn more about it at the end of this article!)
Measuring the Voter Registration Rate
The EPI defines the voter registration rate as the percentage of eligible citizens who report being registered to vote in a state. This step—registering—is the most basic requirement for a voter to be able to cast a ballot, once they meet the requirements for age and citizenship. (In most states, that is; one exception is North Dakota, which does not require voter registration). That’s why it’s included as an indicator. As the EPI methodology states: “If being registered to vote is a prerequisite to voting, then the percentage of eligible voters on the rolls is an important measure of the accessibility of voting.”
In practice, however, voter registration can be harder to quantify than one might expect, due to the variability between states in how they actually maintain their voter registration lists. Each state has a different set of laws and policies that govern their method for—and frequency of—removing deceased residents from voter rolls or identifying and updating the information of voters who have moved. Similarly, states have different policies regarding when voters are able to register to vote or update their voter information. This churn and variability can make it difficult for an index like the EPI to pull and use data directly from the states themselves. To combat this, the EPI calculates the voter registration rate indicator using responses to the Voting and Registration Supplement of the Current Population Survey of the Census, which produces a more stable measure of registration rate over time.
Quantifying the Voter Turnout Indicator
Perhaps the most publicly visible measure of election administration is turnout rate—the percentage of eligible voters who actually cast a ballot in any given election, whether that be for city council or the President of the United States. At a basic level, turnout is considered the total number of people who cast a ballot reported by each state’s election authority divided by the voting eligible population (VEP). The University of Florida Elections Lab calculates and reports the VEP with data going back to the 1700s.
Voter turnout is one of the indicators whose outcomes are most impacted by public policy decisions, legislation, current events, natural disasters, and any other miscellaneous factor that could impact election operations in a state. It is also the one indicator that, at the end of the day, election administrators, academics, and members of the media can only affect so much, as it is entirely up to voters to cast their ballots in their own communities.
That being said, even with this opportunity for variability, “turnout rates are highly correlated across election cycles, reflecting the stability of underlying state-level factors that drive participation,” as the EPI methodology document points out. Simply put, turnout has been largely consistent in midterm and presidential elections, even when the electoral environment has changed.
Voter registration and turnout rates during presidential elections from 2008-2024. Click to enlarge images.
Voter registration and turnout rates during presidential elections from 2008-2024. Click to enlarge images.
The above graphs illustrate both the voter registration rate and voter turnout rates for presidential elections going back to 2008. (Note that the EPI compares presidential elections to previous presidential elections and midterm elections to midterm elections; as a result, the above charts only show presidential elections).
Voter registration rates have remained remarkably stable going back to 2008—staying above the 80% mark even as the election landscape has changed. Turnout is fundamentally a more variable indicator, with shifts both between presidential and midterm election years, as well as when comparing presidential elections to presidential elections. In 2024, turnout fell slightly to 65% nationally, from an all-time high turnout rate of 67.9% during the 2020 elections. Even still, turnout in presidential election years has remained above 60% going back to 2008, showing that even when faced with unprecedented challenges, voters have continued to make their voices heard.
Additional Research is Needed
Over the last few decades, much has changed in our national electoral environment, from the tools used to administer elections to attitudes surrounding voter trust and confidence. But in that same time, academic research examining important areas such as voter registration and list maintenance has not kept up; much of the research into best practices, techniques, and technology is now outdated.
To meet this need, we recently announced a new grant program designed to expand best practices in voter registration and voter list maintenance. More specifically, the ten projects we are providing support for build on strong research practice partnerships, and will draw on the experience of academics and election officials alike. In doing so, the projects will benefit from each team’s collaborative expertise to advance our understanding of how current registration systems operate and develop or encourage innovation in adopting new practices for registration and list maintenance. This research will be conducted through the 2026 midterm election, giving invaluable insights into our electoral environment—and perhaps improving some future iteration of the EPI.
