61% (1974)

56% (1975)

72% (1977)

67% (1971)

66% (1970)

61% (1972)

57% (1971)

46% (1969)

62% (1974)

49% (1970)

55% (1976)

72% (1944)

51% (1970)

32% (1968)

57% (1972)

46% (1969)

47% (1969)

32% (1972)

58% (1968)

59% (1972)