83% (2005)

77% (2003)

79% (1993)

76% (2001)

78% (1995)

84% (1987)

81% (1994)

77% (1993)

79% (1996)

75% (2005)

81% (2005)

67% (1967)

76% (1982)

82% (1998)

78% (1985)

81% (1966)

78% (1970)

66% (1992)

54% (1991)

73% (1982)