72% (2008)

54% (1988)

67% (1977)

61% (1990)

65% (1970)

50% (1995)

74% (1975)

57% (2001)

64% (1976)

56% (2002)

48% (2005)

55% (1981)

51% (1973)

50% (1975)

50% (1998)

50% (1998)

62% (1970)

55% (1996)

38% (1998)

54% (1987)