More than 400 companies have announced plans to invest nearly $1 billion in new or expanded facilities in Maryland by 1987, state economic development officials said today.

The $912 million in capital investment is expected to produce more than 26,000 jobs in the state in the three to five years that will be required to build the new facilities.

Although capital investment commitments fell just short of $1 billion for the first time in four years, the results indicate "we're doing better than our competition," observed James O. Roberson, secretary of the Department of Economic and Community Development.

The new capital investment figures, compiled in a recent survey by the department, are also proof of a "strong, vibrant economy" in the state, despite the national recession, Roberson said at a briefing here.

"If you look at what's happened in Maryland in the teeth of the worst recession since the '30s, it's remarkable," Roberson said.

Although there are strong indications that 1983 should be a good year for economic activity in the state, Roberson said he "would not predict that 1983 will be as good as 1982."

DECD officials said that production increased nearly 9 percent last year in high technology, electronics and textiles, but that declines were recorded in machinery, primary metals and transportation equipment.

Manufacturing employment will continue to decrease in the state this year, but the decline will proceed at a slower rate than the national average, Roberson said. The nonmanufacturing sector--services, transportation, trade and communications--should pick up substantially this year, however.

In the meantime, Roberson said, "If the national economy begins to pick up in the second half, Maryland will follow closely behind."

At least 306 firms plan to invest $594 million in the Baltimore metropolitan area, generating more than 18,000 new jobs.

In the Maryland suburbs around Washington, 68 companies will invest an estimated $209 million for new and expanded facilities, adding about 4,300 jobs to the region's economy.

The combined capital investment in Maryland during the past four years totals about $4.5 billion, resulting in 98,300 new jobs, DECD officials said