81% (1980)

57% (1976)

77% (1989)

77% (1990)

80% (1983)

80% (1980)

64% (1983)

70% (1982)

80% (1981)

68% (1968)

82% (1985)

90% (1981)

80% (1991)

68% (1973)

90% (1968)

50% (1976)

70% (1978)

93% (1990)

70% (1984)

70% (1994)