83% (2005)

82% (2001)

82% (1998)

78% (2003)

79% (2000)

81% (1997)

78% (1996)

74% (1998)

82% (2000)

79% (1999)

71% (2002)

71% (1995)

67% (2001)

69% (1996)

68% (1996)

63% (2002)

80% (1993)

70% (2004)

79% (2002)

66% (1998)