72% (1993)

67% (1980)

68% (1986)

66% (1985)

72% (1981)

70% (1976)

73% (1973)

71% (1982)

65% (1982)

58% (1996)

68% (1967)

51% (2007)

54% (2008)

68% (1977)

74% (1967)

65% (1967)

73% (1974)

70% (1993)

63% (1980)

69% (1980)