58% (1968)

77% (1971)

72% (1972)

77% (1970)

68% (1962)

67% (1972)

63% (1965)

77% (1973)

64% (1974)

71% (1968)

62% (1969)

71% (1970)

67% (1971)

71% (1972)

67% (1974)

78% (1971)

65% (1974)

58% (1971)

63% (1973)

73% (1972)