67% (1979)

58% (1971)

63% (1979)

42% (1955)

52% (1960)

56% (1977)

59% (1973)

30% (1969)

62% (1978)

67% (1973)

68% (1977)

63% (1974)

49% (1977)

66% (1964)

51% (1979)

65% (1963)

59% (1976)

63% (1962)

39% (1971)

51% (1963)