76% (1971)

71% (1975)

59% (1955)

80% (1976)

77% (1967)

76% (1965)

61% (1955)

77% (1970)

72% (1960)

56% (1972)

78% (1977)

72% (1967)

54% (1966)

73% (1971)

71% (1980)

67% (1961)

67% (1964)

70% (1976)

0% (1963)

55% (1956)