72% (1985)

78% (1986)

59% (1988)

71% (1986)

59% (1991)

69% (1986)

66% (1986)

55% (1983)

55% (1989)

60% (1991)

65% (1990)

57% (1990)

57% (1990)

55% (1988)

50% (1986)

56% (1987)

68% (1987)

52% (1990)

63% (1987)