74% (1978)

74% (2008)

57% (1994)

76% (1989)

74% (1994)

74% (1991)

70% (1984)

58% (1995)

70% (1988)

71% (1986)

54% (1992)

65% (1997)

64% (1995)

79% (2002)

72% (2004)

70% (1994)

72% (1991)

62% (1993)

73% (2003)

51% (1992)