50% (1984)

72% (1981)

52% (1978)

42% (1982)

58% (1978)

59% (1977)

49% (1980)

74% (1978)

57% (1985)

60% (1985)

52% (1979)

39% (1982)

52% (1977)

47% (1982)

46% (1991)

58% (1979)

72% (1988)

53% (1977)

50% (1982)

45% (1982)