56% (1972)

61% (1970)

62% (1962)

53% (1974)

59% (1967)

60% (1973)

58% (1973)

60% (1973)

39% (1975)

67% (1967)

54% (1975)

72% (1974)

65% (1973)

53% (1975)

63% (1965)

76% (1970)

51% (1973)

61% (1963)

65% (1975)

63% (1967)