50% (1981)

46% (1980)

50% (1978)

52% (1981)

47% (1974)

52% (1980)

67% (1982)

49% (1979)

46% (1970)

49% (1981)

56% (1977)

45% (1978)

54% (1973)

36% (1974)

53% (1980)

57% (1972)

29% (1970)

24% (1976)

55% (1973)

37% (1978)