28% (1997)

80% (1990)

67% (1972)

51% (2002)

72% (1969)

66% (1984)

61% (1955)

77% (1975)

71% (1983)

78% (1988)

64% (1955)

83% (1973)

65% (1961)

67% (1982)

55% (2003)

70% (1973)

72% (1992)

73% (1971)

70% (1967)

72% (1988)