48% (1982)

78% (1981)

73% (1983)

80% (1979)

70% (1978)

50% (1984)

73% (1984)

65% (1988)

50% (1979)

81% (1981)

63% (1989)

72% (1987)

64% (1987)

60% (1989)

73% (1985)

63% (1988)

70% (1975)

55% (1977)

60% (1984)

72% (1978)