76% (2001)

65% (2004)

61% (1991)

69% (1989)

60% (2002)

56% (2006)

65% (1994)

70% (2004)

66% (2007)

60% (2003)

67% (1994)

59% (2000)

61% (1997)

59% (2008)

54% (1998)

46% (2006)

63% (1993)

54% (1995)

57% (1997)

63% (2005)