75% (2008)

66% (1998)

68% (1990)

72% (1985)

74% (1995)

69% (2003)

72% (1999)

72% (1982)

68% (1993)

62% (1995)

68% (2007)

64% (1991)

63% (2005)

57% (1988)

60% (2001)

69% (1989)

59% (2001)

60% (1986)

71% (1993)

66% (1981)