56% (1975)

67% (1971)

71% (1977)

66% (1970)

61% (1972)

57% (1971)

56% (1976)

46% (1969)

62% (1974)

35% (1968)

57% (1972)

52% (1970)

72% (1944)

62% (1974)

59% (1972)

53% (1969)

49% (1970)

65% (1976)

48% (1970)

62% (1969)