The report, done for a Senate committee, also showed differences by occupation and grade level, which to an extent are linked. The highest ratings overall were for professional employees, who tend to be at higher grade levels, with just 34.4 percent rated only fully successful or below; for administrative employees, that was 38.2 percent; for technical employees 38.7 percent; for clerical 40.1 percent; for blue-collar employees 45.4 percent; and for miscellaneous white-collar employees, 69.4 percent. Meanwhile, the percentage rated only fully successful or below was just 21.7 percent for those in grades GS 13-15; 32 percent for 9-12; and 38.8 percent for grades 1-8. GAO did not state an opinion regarding whether the ratings overall are too high, too low or right, although it did stress that to be effective, ratings must make “meaningful distinctions” between levels of performance, and that agencies must “appropriately reward those who perform at the highest level, and, when necessary, address poor performance. Such distinctions also help employees better understand their relative contributions to organizational success, areas where they are doing well, and areas where improvements are needed,” it said. Lack of a meaningful link between pay and performance is one of the major complaints that federal employees express about their workplace in the annual viewpoint survey.