57% (1988)

58% (1985)

59% (1985)

55% (1986)

58% (1985)

63% (1982)

70% (1988)

55% (1985)

67% (1988)

49% (1983)

55% (1987)

61% (1981)

60% (1987)

54% (1988)

62% (1983)

71% (1988)

72% (1984)

67% (1984)

68% (1987)

34% (1984)