49% (2007)

69% (1997)

73% (1973)

66% (1985)

73% (1966)

74% (1968)

68% (1961)

60% (1968)

65% (1974)

63% (1980)

61% (1977)

80% (1957)

54% (1985)

62% (2007)

74% (1965)

72% (1976)

71% (1970)

73% (1974)

77% (1970)

82% (1959)