60% (1972)

58% (1974)

51% (1969)

78% (1963)

71% (1967)

58% (1970)

68% (1976)

64% (1959)

61% (1972)

59% (1976)

67% (1972)

48% (1971)

53% (1956)

50% (1965)

80% (1954)

69% (1961)

56% (1979)

41% (1954)

22% (1957)

10% (1980)