Convergence of Voter Turnout Rates in U.S. Presidential Elections

Convergence tests are performed on state-level turnout rates for U.S. presidential elections from 1896 to 2004. The degree of dispersion in turnout has steadily declined since 1940, suggestive of general overall convergence taking place. Individually, it is found that 29 of the 48 continental states are stationary in their relative trend levels, and 42 states either do not significantly differ from the national average or are significantly trending toward the national average. In total, 25 of the 48 states pass tests for both stochastic and beta-convergence, suggesting that national convergence is being achieved by roughly half the states.