78% (1976)

77% (1978)

78% (1973)

52% (1968)

57% (1983)

55% (1975)

73% (1981)

55% (1967)

69% (1983)

57% (1974)

67% (1970)

53% (1974)

50% (1972)

67% (1977)

59% (1969)

51% (1969)

49% (1970)

50% (1968)

46% (1975)

50% (1970)