Gauging the health of the electoral process in the United States is an important piece of the work to maintain our democracy overall. One way to do so is to use voter turnout, a seemingly straightforward measure of civic participation that many people believe is the best gauge of the health of our electoral process. Measuring turnout, though, can be more difficult than it first appears. And the complications in measuring turnout also mean that understanding how and why it changes from year to year can also be difficult.

The residual voting rate is used to calculate what percentage of ballots are uncounted in an election; the measure is typically used to assess the performance of election administration features such as ballot design, vote counting, and voting equipment quality.