74% (1987)

59% (1988)

67% (1988)

59% (1989)

56% (1988)

55% (1990)

62% (1989)

60% (1990)

69% (1987)

57% (1986)

52% (1990)

51% (1987)

59% (1989)

61% (1988)

59% (1989)

45% (1988)

44% (1989)

61% (1990)

61% (1987)

55% (1989)