73% (2007)

66% (1974)

68% (1967)

65% (2003)

57% (1991)

72% (1954)

73% (2009)

56% (1986)

61% (1979)

69% (1972)

43% (2011)

58% (1984)

68% (1946)

71% (2005)

60% (2001)

70% (1967)

67% (1993)

58% (1978)

59% (1953)

68% (1965)