74% (1987)

67% (1988)

62% (1988)

59% (1989)

56% (1988)

55% (1989)

61% (1990)

53% (1990)

61% (1987)

59% (1989)

50% (1987)

53% (1990)

43% (1988)

68% (1987)

44% (1989)

58% (1989)

49% (1989)

45% (1988)

58% (1986)

46% (1991)