49% (1977)

66% (1962)

51% (1979)

55% (1977)

50% (1974)

52% (1969)

47% (1977)

54% (1970)

53% (1965)

68% (1977)

72% (1965)

56% (1963)

50% (1976)

53% (1970)

37% (1955)

66% (1963)

57% (1974)

54% (1973)

66% (1964)

47% (1972)