72% (1998)

73% (1990)

75% (2009)

78% (2012)

77% (1969)

72% (1977)

65% (1989)

71% (1992)

71% (2005)

65% (2020)

73% (2000)

75% (1996)

72% (1987)

74% (1973)

68% (1982)

65% (1969)

69% (1990)

66% (2002)

69% (1967)

67% (1974)