82% (2005)

84% (2005)

79% (2004)

79% (2002)

62% (1990)

69% (1999)

81% (2005)

81% (2001)

58% (1988)

69% (2001)

75% (1991)

72% (2006)

66% (1998)

70% (1991)

83% (1993)

55% (2003)

75% (1985)

63% (2006)

63% (1994)

67% (2002)