Year of election Candidates elected # of seats available # of votes % of popular vote
1963 7 108 n.a. 15.5%
1967 20 117 n.a. 25.9%
1971 19 117 n.a. 27.1%
1975 38 125 n.a. 28.9%
1977 33 125 n.a. 28.0%
1981 21 125 n.a. 21.2%
1985 25 125 865,507 23.8%
1987 19 130 970,813 25.7%
1990 74 130 1,509,506 37.6%
1995 17 129 854,163 20.6%
1999 9 103 551,009 12.6%
2003 7 103 660,730 14.7%
2007 10 107 741,043 16.8%
2011 17 107 980,204 22.73%