50% (1985)

62% (1971)

57% (1990)

49% (1985)

57% (1981)

72% (1971)

62% (1972)

51% (1983)

58% (1987)

50% (1979)

52% (1987)

41% (1990)

38% (1977)

59% (1989)

63% (1972)

62% (1972)

53% (1987)

50% (1972)

60% (1970)

58% (1971)