81% (1979)

82% (1986)

77% (1982)

77% (1987)

65% (1982)

60% (1976)

50% (1989)

80% (1982)

72% (1976)

85% (1985)

66% (1978)

72% (1990)

62% (1983)

52% (1989)

64% (1980)

48% (1988)

48% (1980)

58% (1983)

78% (1976)

63% (1978)