77% (1997)

80% (1997)

80% (1987)

79% (1990)

77% (1992)

73% (1989)

76% (1991)

73% (1974)

71% (1984)

65% (1979)

56% (1975)

66% (1970)

62% (1973)

20% (1980)

57% (1976)

61% (1972)

55% (1995)

50% (1983)

42% (1977)

67% (1996)