63% (1974)

65% (1977)

57% (1971)

64% (1976)

70% (1975)

60% (1979)

50% (1975)

0% (1976)

75% (1984)

55% (1983)

73% (1982)

50% (1974)

70% (1980)

50% (1981)

57% (1981)

40% (1978)