74% (1992)

54% (1983)

30% (1991)

55% (1987)

73% (1993)

69% (1986)

39% (1980)

31% (1997)

54% (1977)

57% (1980)

52% (1997)

73% (1989)

47% (1982)

27% (1996)

52% (1999)

58% (1992)

69% (1981)

35% (1981)

60% (1995)

52% (1984)