57% (1980)

73% (1979)

74% (1982)

60% (1991)

45% (1986)

56% (1996)

52% (1996)

77% (1982)

54% (1980)

57% (1991)

52% (1986)

77% (1988)

58% (1998)

45% (1992)

70% (1989)

72% (1994)

75% (1993)

35% (1987)

59% (1984)

43% (1992)