72% (1981)

74% (1978)

60% (1985)

51% (1978)

52% (1978)

53% (1979)

53% (1977)

45% (1979)

42% (1982)

54% (1987)

52% (1979)

72% (1988)

58% (1979)

50% (1984)

50% (1978)

50% (1982)

64% (1978)

39% (1982)

59% (1977)

50% (1979)