67% (1972)

65% (1975)

50% (1983)

64% (1974)

74% (1985)

60% (1975)

70% (1975)

57% (1976)

83% (1977)

64% (1983)

45% (1979)

59% (1982)

67% (1978)

57% (1986)

67% (1982)

40% (1983)

67% (1984)

62% (1976)

82% (1976)

45% (1985)