62% (1985)

63% (1987)

56% (1986)

63% (1979)

63% (1989)

42% (1978)

55% (1987)

52% (1981)

56% (1974)

56% (1984)

57% (1972)

40% (1978)

48% (1983)

59% (1985)

55% (1990)

48% (1974)

62% (1988)

53% (1985)

57% (1978)

67% (1985)