57% (1976)

67% (1974)

53% (1973)

60% (1975)

59% (1973)

54% (1974)

68% (1972)

57% (1974)

0% (1976)

68% (1976)

55% (1972)

52% (1972)

53% (1976)

55% (1974)

33% (1977)

0% (1979)

58% (1974)

55% (1975)

55% (1973)

66% (1973)