(FORTUNE Magazine) – Uncle Sam wants MBAs for careers in public service, but yuppies are not ! signing up. The Yale School of Organization and Management, which celebrates its tenth anniversary November 15, has fallen far short of its initial goal of placing a large number of its students in government jobs. This year about 110 of 127 graduates polled opted for high-paying private sector careers. A recent Yale survey found that only 24 of the 311 alumni polled shifted from private industry to government and nonprofit jobs. One problem is skimpy government salaries. A government study shows that between 1969 and 1984, the purchasing power of white-collar civil service workers went down 4% and that of members of Congress and high-ranking officials in the executive branch dropped 39%. Over the same period, corporate executives boosted their purchasing power an average 68%. President Reagan wants to tie government pay to performance, not seniority, and scrap the federal hiring manual, which covers more than five feet of shelf space in the Office of Personnel Management. A special presidential commission, headed by James Ferguson, chairman of General Foods, is studying the salaries of congressional and top-level federal executives and may recommend substantial increases late this year.