73% (1975)

55% (1971)

71% (1963)

75% (1963)

73% (1964)

77% (1964)

67% (1965)

61% (1973)

77% (1967)

56% (1972)

53% (1975)

59% (1967)

63% (1965)

58% (1965)

75% (1970)

65% (1973)

68% (1974)

61% (1970)

54% (1974)

61% (1963)