73% (1982)

70% (1983)

72% (1981)

72% (1979)

68% (1981)

67% (1983)

45% (1979)

69% (1982)

67% (1980)

50% (1981)

51% (1981)

52% (1980)

65% (1983)

59% (1980)

48% (1981)

64% (1980)

58% (1982)

0% (1983)