57% (1980)

73% (1979)

77% (1988)

56% (1991)

60% (1991)

59% (1984)

73% (1989)

72% (1994)

62% (1984)

41% (1997)

83% (1981)

69% (2000)

52% (1996)

75% (1993)

52% (1989)

77% (1982)

68% (1988)

74% (1982)

75% (1985)

47% (1994)