Percentage change in voters, electors and turnout for each dyad
Percentage Changes in Voters, Electors, and Turnout Between Election Cycles
Dyad Change_in_Voters Change_in_Electors Change_in_Turnout
1967-1971 -0.3528737 8.754136 -8.0721821
1980-1984 17.5197464 5.225579 11.5053989
1984-1989 27.8896943 31.538716 -2.8417543
1991-1996 21.1120937 18.780720 -32.2279351
1999-2004 7.6536829 9.228898 -0.7414461

Only 1967-71 sees a decrease in absolute voters.