83% (2005)

78% (2003)

81% (1997)

82% (2001)

73% (1998)

79% (2000)

79% (1996)

81% (1993)

82% (1998)

71% (2002)

79% (1999)

77% (1996)

65% (1995)

72% (1994)

72% (2008)

69% (2001)

79% (2002)

71% (1995)

67% (1996)

81% (1999)