66% (1951)

65% (1961)

78% (1969)

77% (1962)

72% (1960)

59% (1969)

64% (1958)

66% (1959)

64% (1961)

47% (1960)

70% (1956)

37% (1971)

63% (1955)

74% (1959)

50% (1971)

40% (1973)

63% (1957)

66% (1956)

58% (1953)

56% (1971)