88% (1994)

86% (1999)

80% (1995)

68% (2004)

67% (2011)

55% (1996)

66% (2000)

64% (2002)

75% (1989)

78% (1990)

63% (2010)

56% (2003)

73% (2007)

61% (1995)

79% (2004)

58% (2005)

70% (1993)

67% (2007)

76% (2013)

53% (2003)