56% (1994)

56% (1992)

69% (1980)

74% (1994)

73% (1972)

37% (1998)

65% (1985)

69% (1993)

65% (1997)

71% (1992)

70% (1988)

68% (1995)

69% (1992)

66% (1996)

64% (1996)

63% (1990)

67% (1990)

71% (1991)

75% (1973)

72% (1988)