64% (1971)

71% (1972)

32% (1970)

65% (1951)

54% (1975)

46% (1973)

39% (1973)

44% (1973)

53% (1971)

46% (1971)

43% (1978)

46% (1980)

44% (1979)

45% (1972)

50% (1973)

53% (1979)

50% (1970)

50% (1975)

43% (1977)