72% (1966)

77% (1959)

61% (1960)

50% (1970)

78% (1956)

64% (1963)

72% (1975)

67% (1971)

70% (1971)

64% (1964)

70% (1958)

67% (1961)

61% (1962)

65% (1963)

64% (1966)

64% (1968)

69% (1964)

69% (1967)

40% (1973)

50% (1971)