If you think you are underpaid in your government clerical, technical or administrative job in Washington, Baltimore, Philadelphia or Norfolk, there is a reason:

You are being paid about 20 percent less than your private-sector counterpart, according to a new congressional study.

The pay matchup of federal and private salaries by the General Accounting Office in more than 60 metropolitan areas showed that 90 percent of the time the government is paying people less than they would get if they had the same job in private industry. In instances where government workers had the salary edge, it usually was less than 5 percent.

GAO's study of 1987-88 pay rates produced the following conclusions for nearby cities with large numbers of federal workers:

For the Washington metropolitan area, GAO matched pay for 11 job categories. In all 11 cases, GAO found that private industry was paying more than the government rate for that job. The median advantage, GAO said, was 21.9 percent.

In 18 of 20 job matches in Baltimore, private industry paid about 22 percent more than the government. In the two jobs where the government paid more, the median advantage was 4 percent.

GAO also made 18 job and pay matches between government and private pay in Philadelphia. In all 18 instances industry paid more -- an average of 19.4 percent more -- than the government.

In the Virginia Tidewater area of Norfolk, Virginia Beach and Newport News, GAO compared 12 jobs. In six the government paid more than industry (about 5.3 percent more), while in six industry paid about 11.1 percent more.

In Richmond, the GAO compared pay for 13 jobs. For 10 of the jobs, the private sector paid about 15 percent more. The government paid about 3.5 percent more than industry in three other job categories.

The jobs surveyed in the study included file clerk, stenographer, secretary, computer operator, computer programmer, computer systems analyst, key entry operator, accounting clerk and drafter.

GAO's study is for William D. Ford (D-Mich.). His Post Office and Civil Service Committee is working on changes that would make government salaries more competitive.

The Bush administration wants pay changes that include an 8 percent differential for federal workers in New York, Los Angeles and San Francisco, where the pay gaps are widest.

Several members of Congress want a city-by-city pay differential plan. Rep. Constance A. Morella (R-Md.) and Sen. Barbara A. Mikulski (D-Md.) are pushing for the 8 percent differentials for workers here and in Baltimore.

U.S. Workers in Politics

The House today is expected to approve a Senate-passed bill that would give federal workers more leeway to participate in partisan politics off the job. The House earlier passed a much more liberal political action plan but has decided to go with the less-controversial Senate plan in hopes of avoiding a veto.