79% (1997)

80% (1987)

77% (1997)

20% (1980)

79% (1990)

77% (1992)

65% (1979)

76% (1991)

74% (1989)

0% (1977)

58% (2000)

62% (1972)

66% (1974)

65% (1970)

62% (1973)

42% (1977)

67% (1996)

56% (1981)

72% (1974)

40% (1983)