56% (1987)

71% (1981)

45% (1982)

51% (1984)

67% (1979)

30% (1979)

46% (1980)

33% (1985)

47% (1981)

60% (1979)

52% (1984)

45% (1987)

53% (1978)

10% (1952)

38% (1983)