88% (1994)

86% (1999)

81% (2010)

80% (1995)

67% (2011)

68% (2004)

75% (1989)

78% (1990)

73% (2007)

65% (2000)

64% (2010)

79% (2004)

64% (2002)

56% (1996)

75% (2013)

67% (2007)

58% (2005)

70% (1993)

67% (1997)

57% (2003)