54% (1977)

68% (1976)

65% (1982)

59% (1976)

58% (1978)

66% (1978)

57% (1983)

62% (1978)

62% (1979)

47% (1976)

60% (1984)

62% (1978)

59% (1983)

80% (1986)

58% (1979)

0% (1976)

80% (1986)

0% (1984)

0% (1984)

70% (1985)