73% (1973)

57% (1974)

53% (1971)

65% (1976)

50% (1974)

54% (1968)

67% (1986)

63% (1971)

49% (1975)

69% (1979)

43% (1970)

54% (1967)

32% (1972)

52% (1970)

58% (1969)

59% (1979)

59% (1977)

38% (1981)

62% (1976)

38% (1972)