74% (1993)

70% (1992)

50% (2003)

77% (1987)

58% (1996)

57% (2009)

63% (2005)

61% (1990)

60% (2000)

77% (1969)

55% (1979)

52% (1995)

62% (1983)

55% (1984)

66% (2005)

58% (1981)

57% (1988)

57% (1989)

49% (2007)

65% (1965)