58% (1986)

43% (1989)

56% (1983)

48% (1974)

52% (1986)

58% (1978)

53% (1982)

49% (1988)

52% (1985)

51% (1971)

46% (1972)

40% (1988)

47% (1988)

52% (1976)

44% (1983)

44% (1988)

45% (1985)

55% (1990)

41% (1985)

60% (1974)