74% (1996)

76% (1981)

71% (1982)

75% (1970)

72% (1982)

74% (1972)

73% (1977)

75% (1978)

68% (1978)

62% (1974)

56% (1990)

60% (1984)

50% (1983)

50% (1988)

50% (1979)

53% (1990)

50% (1987)

60% (1990)

50% (1977)

81% (1994)