35% (1968)

46% (1980)

63% (1974)

65% (1986)

76% (1980)

83% (1984)

80% (1986)

65% (1983)

90% (1970)

64% (1980)

90% (1968)

58% (1991)

50% (1974)

60% (1969)

73% (1977)

75% (1989)

70% (1983)

77% (1989)

58% (1977)

95% (1984)