44% (1974)

60% (1980)

46% (1975)

50% (1983)

45% (1961)

37% (1985)

46% (1980)

43% (1962)

36% (1973)

53% (1973)

58% (1987)

46% (1977)

48% (1985)

53% (1985)

34% (1969)

59% (1986)

65% (1980)

53% (1982)

55% (1984)

41% (1980)