62% (1985)

42% (1978)

63% (1984)

57% (1988)

54% (1980)

55% (1987)

57% (1972)

57% (1988)

55% (1976)

59% (1984)

48% (1983)

56% (1976)

58% (1980)

56% (1986)

56% (1971)

63% (1979)

64% (1977)

62% (1988)

56% (1988)

48% (1974)