66% (1981)

58% (1988)

59% (1984)

43% (1983)

48% (1984)

63% (1980)

59% (1984)

55% (1986)

55% (1983)

59% (1983)

64% (1984)

51% (1987)

60% (1987)

46% (1987)

63% (1980)

71% (1979)

62% (1981)

62% (1983)

50% (1988)

56% (1979)