The issue, on which the General Accounting Office and the Office of Management and Budget rather vigorously disagree, is how the federal government decides the number of employes it needs.

GAO thinks everybody should sit down, study industrial engineering manuals, learn how to match up bodies with work to be done, and let that number be the one that counts. That's called work force planning.

OMB likes a new system called the full-time equivalent personnel ceiling (FTE), a system that took effect governmentwide on Oct. 1 after a test run in five agencies. For reasons to be explained later, FTE makes some people nervous, particularly at the Defense Department, which is exempt from FTE.

The issue is argued with a good deal of steam, heat and oratory because its outcome determines not only how many people will work for Uncle Sam, but whether they will be carried on the books straightforwardly as employes, or whether they will be hidden as full-time part-timers or contract employes.

Regardless of what policy is used, it is certain to be a compromise between politics (the president promises to cut the federal work force) and money (the government manager has a certain amount to spend and divides it between people and programs, just as he would if he were running a business).

For years the official size of the federal work force has been determined more by politics. Personnel levels were established in the hoary past for reasons long forgotten, then frozen or cut or expanded depending on the times and the means.

The measure of how accurately the agreed-upon levels were being met was the "end-of-year personnel ceiling," which meant that on the last day of the fiscal year (Sept. 30), the personnel level could not exceed a certain number.

That left federal managers only 364 days a year to mess with the numbers. They hired a lot of part-timers on the first day of the new fiscal year, then fired them on the second-to-the-last day (before rehiring them again). The Forest Service once fired 7,000 employes in the last week of a fiscal year.

This "hidden federal work force" reached unknown proportions every year before disappearing on counting day. The president could point with pride to the official count and say, "See, I've held down federal employment just as I promised."

Contracting is another technique used to increase employment. Since managers generally have more money than they need to pay the authorized people, they hire contractors to get the job done.

The GAO, in reviewing the fiscal 1980 budget, estimated that the cost of the direct federal work force was $111.2 billion, including $58.1 billion for defense. But the indirect or contracted work force was $72.6 billion--more than either the military or civilian sectors.

This brings us back to the full-time equivalent personnel ceiling and work force planning. On Oct. 1 the government replaced year-end personnel ceilings with FTE. Personnel allocations, instead of being expressed in numbers of people, are stated as numbers of full-time work years an agency can spend.

If X hours are spent on summertime employes to trim shrubs in the national parks, the total hours against which the Interior Department can draw is reduced. Thus FTE should, everyone agrees, make it harder to jigger the numbers.

The Defense Department, which has a huge civilian work force of variable size, was not enthusiastic about FTE and it won an exemption from it in Congress. "They objected because FTE is a tougher control," an OMB official groused.

It may be tougher, but it does little to resolve the contracting question. As a knowledgeable congressional staffer noted, "President Reagan froze federal employment, but he did not freeze contracting. You have a political force pressure for reduction in federal employes creating bad management."

In the view of Rep. Geraldine A. Ferraro (D-N.Y.), chairman of the House Civil Service subcommittee on human resources, "There is no relationship between allocated ceilings and the job the agency is asked to do. You ought to have a budget line item for all employment, direct and indirect."

GAO thinks that FTE is a better management tool than year-end personnel ceilings, but that work force planning would be better yet because it addresses contracting. If the amount of work to be done is properly defined, the number of employes can be accurately set within the personnel budget. The money available would be the control. If there is not enough money, everybody knows it up front, adjustments are made and surprises disappear.

Work force planning has the disadvantage of producing employment numbers which might be politically unacceptable. Further, according to both OMB and Office of Personnel Management officials, GAO's push for work force planning and a consistent, across-the-board approach to personnel-level setting is unrealistic.

"It's one thing to say how many travel vouchers can be processed in one hour, and thus come up with the correct number of travel voucher processors," an OMB official said. "But what about lawyers? Caseload isn't meaningful as a measure of work; if it was, the lawyers would litigate only the easy cases and would leave alone the hard ones that take a long time."

"Besides," the official went on, "we have basic workload justifications built in" to budget planning.

What about GAO's proposal that OMB and OPM design a work force planning manual and impose it on the entire government?

"If the GAO wants to come up with a manual on work force planning," he said, "we'll look at it."