65% (1999)

73% (2004)

71% (1992)

68% (1986)

70% (2001)

73% (1992)

63% (1997)

57% (1990)

57% (1996)

55% (2008)

63% (1988)

46% (2008)

56% (1991)

62% (1988)

70% (2005)

65% (1989)

61% (1990)

61% (2009)

42% (1986)

43% (2003)