57% (1976)

43% (1982)

41% (1978)

69% (1975)

66% (1976)

53% (1975)

67% (1979)

69% (1976)

55% (1978)

50% (1978)

47% (1975)

59% (1978)

62% (1978)

48% (1979)

56% (1977)

60% (1976)

60% (1981)

47% (1976)

51% (1976)

58% (1975)