71% (1989)

57% (1976)

41% (1978)

50% (1978)

46% (1983)

52% (1973)

63% (1969)

38% (1977)

54% (1972)

45% (1983)

42% (1980)

50% (1973)

62% (1970)

48% (1980)

62% (1970)

50% (1973)

50% (1997)

42% (1972)

42% (1975)

50% (1962)