62% (1963)

67% (1959)

67% (1968)

61% (1964)

68% (1966)

61% (1970)

64% (1969)

63% (1964)

71% (1961)

56% (1964)

59% (1972)

59% (1966)

56% (1976)

61% (1971)

66% (1958)

58% (1971)

59% (1971)

59% (1974)

60% (1970)

62% (1970)