If it weren't for the OPEC nations and Jimmy Carter, Washington area residents could expect a 1977 that would be virtually an economic carbon copy of 1976.

According to several observers of the capital region's economy, the international oil cartel and the Presidentelect provide one common element: uncertainty.

If it weren't for that factor, the observers agree, there would be continued sluggish recovery from the downturn of recent years, with regional employment remaining stable and with less unemployment than nationally.

"We don't see anything on the horizon to make us expect our unemployment rate to go up," said John Tydings, assistant executive vice president of the Metropolitan Washington Board of Trade.

"The general feeling is one of pretty cautious optimism," Tydings continued, "the caution being predicated on what happens with the new (Carter) administration and the directions it sets, as well as on the energy problem."

The most recent jobless figures, issued Dec. 22 for November, showed rates of 5.2 per cent for the metropolitan area and 7.1 per cent for the District of Columbia compared with 8.1 per cent nationwide.

Atlec E. Shidler, president of the Washington Center for Metropolitan Studies, said the Washington area "needs somebody with the necessary resources to pay more attention to the (available economic) data, to focus more on interpretation."

In the past, Shidler said, the Washington area has ridden the crest of the expansion of the federal government, so it was not "pressed so hard by economic crises." That, he said, has now changed.

Bill Cook, an economist who is assistant director of the D.C. Department of Finance and Revenue, said he foresees a rise in city residents' personal income totaling about 7 per cent over the this year and 1978. If one included all persons who works in the city, the rise would be about 8 per cent, reflecting the higher average salaries of suburbanites, Cook said.

"With the structure of the D.C. economy - service-oriented, professionally oriented, government-oriented - a national recession does not hurt here as much as anywhere else," Cook said. "Conversely, we do not share in the up-side as much as others."

For property owners in the region, the tax situation is unclear. The D.C. City Council has adopted a revenue package for the fiscal year starting next Oct. 1 that does not include any rises in broad-based taxes. Both Maryland and Virginia foresee revenues at current tax rates falling short of projected expenditures, but the politicians have not settled on solutions.

Suburban cities and counties have not yet begun to deal with the next fiscal year's budgets and tax rates.

Under the projections of the outgoing Ford administration, the federal government - which remains the region's primary employer - would keep its civilian work force at about the current level. Of 2.5 million employees nationally, some 350,000 work in this area.)

Although the Democrats generally are regarded as more inclined toward increasing the role - and the size - of government, the anti-Washington rhetoric of Carter's campaign sent a nervous shiver through the bureaucracy. It raised cautionary signs among economic observers.

Even some subtleties of Carter's policies, if put into effect, could reverberate through this region's economy.

For example, Michael C. Fox, head of an Arlington realty firm and the new president of the Northern Virginia Board of Realtors, foresees a good year to buy and sell homes. He said there has been some localized leveling of cost increases, but values generally continue upward.

Fox said this is due in part to "the usual military transfers," which rotate personnel into and out of the Pentagon and other area installations.

Carter has spoken, however, of the possibility of saving military personnel costs by reducing the frequency of such transfers - which therefore would reduce the turnover of homes.

Although the policies of the oil cartel are felt internationally, the price and availability of fuel has a direct local impact that can be noted in several ways.

Austin Kenny, executive vice president of the Washington Area Convention and Visitors Association, said gasoline prices are among economic factors that "can either heighten or dampen the amount of tourist traffic we get."

If national economic conditions continue to improve and gasoline prices remain fairly stable, Kenny said he foresees that "we might even do better with tourism in 1977 (than in the Bicentennial year of 1976) for a couple of reasons."

The first year of any national administration is a good one for trade association conventions, Kenny said, and 1977 should be no exception.

John T. O'Neill, executive vice president of the 1,000-member Apartment and Office Building Association, said his industry expects energy costs - principally for heating and lighting - to increase by about 15 per cent, in addition to steep rises in sewer and water costs.

"I would venture that most (apartment) tenants will have to expect somewhere around a 6 to 8 per cent rent increase in 1977, fairly comparable to the past two years," O'Neill said.

O'Neill said he foresees a rental crisis in the District of Columbia, where rent control is in effect and, he said, 24 per cent of all projects are paying out more money in costs than they are taking in from rents.

All of the utility companies in the area have gone through a cycle of rate increases, virtually clearing the dockets of regulatory agencies.Transit riders can expect three jumps in fares during the year - a bus fare rise on suburban lines in February, a new combined rail-bus fare structure in July and a potential rise of both bus and rail fare late in the year.

In 1976, the Chesapeake & Potomac Telephone Cos. reported a 3.3 per cent growth rate, which translates to about 92,000 new telephones. They anticipate adding another 96,400 in 1977.

W. Reid Thompson, chairman and president of the Potomac Electric Power Co., said he expects growth in 1977 "to be significantly reduced from what we have experienced in recent years." Among other factors, he cited uncertainty over the proposed Dickerson wastewater plant in Montgomery County, rejected by the U.S. Environmental Protection Agency. The plant would accommodate regional growth.