From 1951 to 1971, instead of 12 senators elected every three years, the electorate voted for eight senators every two years in the same format. From 1941 to 1949, all elections to the senate were by block voting: the voters may write a name for every seat contested, or they can write the name of the party, which would then give all of the voters' votes to that party's ticket. Compounded with the Nacionalista Party's dominance, this caused a sweep of 24 seats for them in 1941. From 1916 to 1934, voting was via senatorial districts; voters vote for one candidate every three years, except for the first election in 1916 where they'd vote for two candidates; the second-placed candidate would only serve for three years.