50% (1983)

73% (1988)

52% (1984)

42% (1987)

59% (1985)

54% (1989)

61% (1985)

59% (1987)

39% (1981)

58% (1985)

38% (1976)

44% (1980)

54% (1985)

63% (1988)

30% (1983)

53% (1980)

71% (1988)

37% (1987)

50% (1980)

40% (1988)