60% (1971)

65% (1974)

54% (1983)

57% (1971)

57% (1977)

39% (1980)

30% (1977)

53% (1974)

50% (1975)

40% (1978)

0% (1976)

0% (1971)

50% (1981)

65% (1971)

40% (1980)

50% (1982)

60% (1970)

76% (1977)

60% (1975)

0% (1979)