59% (1960)

77% (1971)

61% (1960)

60% (1970)

46% (1967)

57% (1969)

69% (1961)

68% (1966)

74% (1950)

60% (1974)

59% (1964)

58% (1966)

54% (1960)

50% (1973)

69% (1963)

50% (1974)

56% (1965)

78% (1968)

86% (1968)

59% (1958)