age in years
=1 if white non-Hisp, =2 if black non-Hisp, =3 if Hispanic
years of competed education
=1 if in union, =2 otherwise
=1 if largest 19 smsa, =2 if other smsa, =3 not in smsa
=1 if northeast, =2 if midwest, =3 if south, =4 if west
usual weekly earnings, up to $999