70% (1992)

64% (1981)

56% (1985)

62% (1982)

76% (1986)

74% (1982)

74% (1990)

73% (1988)

76% (1989)

71% (1987)

74% (1991)

58% (1992)

61% (1983)

77% (1986)

60% (1984)

74% (1985)

54% (1992)

56% (1983)

68% (1988)

56% (1979)