78% (1986)

72% (1985)

69% (1986)

66% (1986)

56% (1983)

59% (1991)

59% (1988)

55% (1989)

71% (1986)

61% (1991)

57% (1990)

55% (1988)

57% (1990)

64% (1990)

68% (1987)

50% (1986)

62% (1987)

53% (1987)

52% (1990)