83% (2005)

84% (2005)

80% (2004)

79% (2002)

81% (2005)

80% (2001)

69% (2001)

75% (1991)

75% (1985)

67% (2002)

53% (2003)

71% (2006)

65% (1998)

55% (2003)

83% (1993)

61% (1990)

64% (1994)

63% (2006)

58% (1988)

77% (2005)