Voter turnout

Voter turnout is the percentage of eligible voters who cast a ballot in an election. Eligibility varies by country, and the voting-eligible population should not be confused with the total adult population. Age and citizenship status are often among the criteria used to determine eligibility, but some countries further restrict eligibility based on sex, race, and/or religion.

After increasing for many decades, there has been a trend of decreasing voter turnout in most established democracies since the 1980s. In general, low turnout is attributed to disillusionment, indifference, or a sense of futility (the perception that one's vote won't make any difference).

Low turnout is usually considered to be undesirable. As a result there have been many efforts to increase voter turnout and encourage participation in the political process. In spite of significant study into the issue, scholars are divided on the reasons for the decline. Its cause has been attributed to a wide array of economic, demographic, cultural, technological, and institutional factors.

Different countries have very different voter turnout rates. For example, turnout in the United States 2012 presidential election was about 55%. In both Belgium, which has compulsory voting, and Malta, which does not, participation reaches about 95%.

The chance of any one vote determining the outcome is low. Some studies show that a single vote in a voting scheme such as the Electoral College in the United States has an even lower chance of determining the outcome. Other studies claim that the Electoral College actually increases voting power. Studies using game theory, which takes into account the ability of voters to interact, have also found that the expected turnout for any large election should be zero.

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