60% (1983)

51% (1976)

45% (1977)

47% (1976)

59% (1978)

70% (1978)

51% (1983)

53% (1975)

49% (1975)

31% (1976)

50% (1975)

57% (1977)

58% (1975)

46% (1974)

57% (1976)

48% (1977)

60% (1975)

47% (1976)

52% (1982)

61% (1981)