50% (1987)

55% (1986)

60% (1986)

50% (1988)

30% (1981)

60% (1985)

52% (1985)

50% (1981)

80% (1984)

35% (1986)

78% (1987)

60% (1981)

56% (1987)

47% (1987)

58% (1984)

80% (1988)