58% (1973)

48% (1970)

59% (1972)

56% (1958)

47% (1974)

50% (1974)

54% (1966)

48% (1957)

53% (1967)

38% (1958)

52% (1974)

51% (1979)

46% (1959)

40% (1978)

58% (1976)

52% (1976)

34% (1980)

65% (1975)

56% (1965)

40% (1961)