70% (2001)

65% (1999)

70% (1992)

71% (2005)

72% (2004)

64% (1988)

56% (1996)

73% (1992)

68% (1986)

56% (1991)

60% (1990)

62% (1988)

63% (1997)

55% (2008)

64% (1989)

53% (2003)

57% (1990)

40% (1989)

46% (2008)

65% (1998)