74% (1997)

51% (2001)

64% (1986)

63% (1988)

70% (1992)

58% (1983)

74% (2002)

58% (1995)

52% (2004)

58% (1992)

64% (1990)

57% (1990)

69% (1995)

66% (2002)

65% (1986)

50% (1990)

65% (1991)