53% (1980)

73% (1988)

53% (1983)

38% (1985)

60% (1988)

50% (1986)

63% (1979)

45% (1984)

62% (1984)

55% (1986)

40% (1984)

49% (1985)

49% (1987)

54% (1983)

59% (1987)

61% (1987)

44% (1986)

61% (1985)

40% (1985)

54% (1980)