63% (1979)

50% (1989)

66% (2009)

58% (2002)

62% (1979)

59% (1995)

43% (2007)

76% (2003)

57% (1983)

67% (1976)

58% (2008)

61% (2007)

51% (2003)

56% (1979)

54% (1981)

71% (1977)

65% (1977)

69% (2005)

70% (2005)

50% (1985)