In the United States, the Election Assistance Commission collects data on the administration of federal elections through the Election Administration and Voting Survey (EAVS). Data from EAVS are essential to understanding how states and localities run elections and are a key part of Pew’s Elections Performance Index. On the other side of the Atlantic, the United Kingdom Electoral Commission gathers a large amount of similar elections data.
Both the U.K. and U.S. data sets include information on registered voters; total participation; and mail ballots sent, returned, and rejected. Although complete data from the May 2015 election are not yet available, those from previous U.K. elections show that, as in the U.S., voting by mail is on the rise, with nearly 1 in 5 ballots cast by mail in 2010, compared with 1 in 20 in 2001.
The U.K. Electoral Commission also collects data on the total overvotes and undervotes cast and the number of individuals who tried to register to vote after the deadline had passed. An overvote occurs when a person casts more than one vote in a single contest, and an undervote happens when a person does not vote for every contest on the ballot.
Data sets are available to download, and the commission issues a report describing and analyzing the data after each election, noting trends and changes. Additionally, the commission has conducted a number of public opinion surveys about voter experiences and detailed assessments of its voter registration system, and it has tackled the challenging task of estimating the total cost of running an election.