Cluster analysis grouped 621 jobs into 6 "contours" showing that from 1973-1990 employment distribution shifted away from 2 middle-quality to the 2 highest-quality contours; no change was apparent in the 2 lowest quality. Black and Hispanic men were affected by a worsening job mix and drop in the quality of low-skill jobs. Women experienced a shift away from lowest-quality contours and higher real earnings growth within each contour. (SK)