71% (1992)

77% (1986)

74% (1982)

76% (1986)

62% (1983)

74% (1991)

58% (1992)

74% (1990)

75% (1989)

74% (1985)

61% (1984)

68% (1988)

57% (1983)

57% (1985)

70% (1981)

66% (1982)

73% (1988)

62% (1986)

38% (1987)

65% (1985)