47% (1984)

66% (1981)

43% (1983)

71% (1979)

61% (1983)

59% (1984)

63% (1982)

63% (1977)

61% (1985)

42% (1986)

62% (1980)

64% (1980)

58% (1988)

62% (1981)

55% (1983)

63% (1985)

76% (1980)

52% (1971)

52% (1982)

58% (1983)