The Washington area gained about 26,000 new jobs last year, a 1.7 percent increase in employment that was almost twice the national average.

The gain was small when compared to the growth in jobs in Sun Belt cities like Dallas and Houston. But the new figures from the U.S. Bureau of Labor Statistics suggest there is truth to the notion that Washington's government and service-based economy is recession-proof compared to northern cities that are heavily dependent on manufacturing.

Figures for the District of Columbia show that despite last year's cutbacks by city government, private employers created enough new positions to increase the overall number, holding at bay an overall decline in jobs that occurred in the mid-1970s.

These findings emerged from examination of statistics on the average number of nonagricultural jobs available in a given jurisdiction in calendar 1980 as compared to calendar 1979. the conclusions do not necessarily mean lower rates of unemployment, because the labor force was expanding at the same time.

The number of jobs in the Washington area has increased steadily for the last five years, but at varying rates. In 1979, for example, the increase was 4.5 percent, according to figures compiled by the D.C. Department of Employment Services.

Last year's growth was due to new jobs in the area's manufacturing, transportation, retail and wholesale, finance, real estate, and services industries. Federal employment rolls also grew, reaching 365,900 for an increase of 4,400 in the area.

Even though construction firms and local and state governments reduced their manpower, the net result for the area was a gain of about 25,800 jobs, bringing the total to 1,571,100.

The area, as defined by the Bureau of Labor Statistics, includes the following jurisdictions: the District of Columbia, Prince George's, Montgomery and Charles counties in Maryland; the towns of Alexandria, Fairfax, Falls Church, Manassas and Manassas Park, and Fairfax, Arlington, Prince William and Loudoun counties in Virginia.

Despite the rhetoric of last fall's presidential campaign, the figures show no proliferation in federal employment rolls in the Washington area. In fact, federal agencies' manpower here rose only 1.2 percent over 1979, a rate about one-third lower than the area's rate as a whole.

The District's record has been less successful however. New businesses tend to favor the suburbs. One D.C. official remarked, "Most of the increase would be in the suburban ring. The District is landlocked."

Total numbers of jobs actually declined slightly in 1975 and 1976, but then began a gradual climb upward. In 1980 the average number of positions grew by about 0.46 percent -- less than one-third of the area's rate -- to reach 615,300, the departmenths figures show.

That gain resulted from new jobs in service, financial and manufacturing concerns in the district. Federal employment increased only marginally, to just over 228,000 in the city. Growth in these sectors offset declines in the transportation, retail, wholesale and construction industries and in city government offices where a total of about 2,900 positions were eliminated.

Metropolitan New York's growth rate was a little less than half of the Washington area's -- 0.8 percent -- while Chicago's grew by 0.6 pecent, Los Angeles' by 1 percent and San Francisco's, 2.7 percent.

Certain Sun Belt cities, however, showed a greater growth in employment. Dallas and its suburbs had a 5 percent increase in jobs; Houston, 4 percent.