74% (1992)

55% (1983)

55% (1987)

30% (1991)

69% (1986)

57% (1980)

73% (1989)

31% (1997)

58% (1993)

40% (1987)

50% (1982)

74% (1993)

54% (1991)

52% (1984)

52% (1997)

54% (1977)

50% (1988)

54% (1990)

47% (1982)

35% (1981)