64% (1978)

71% (1975)

67% (1976)

60% (1984)

71% (1971)

53% (1973)

59% (1981)

71% (1968)

64% (1974)

82% (1974)

63% (1979)

58% (1976)

54% (1973)

58% (1979)

56% (1973)

39% (1971)

46% (1973)

52% (1982)

54% (1973)

46% (1971)