PORTLAND – After 12 years of a downward spiral, the population in the state’s northernmost county appears to have reached bottom and may be poised to regain lost ground, according to census data.

Population estimates show Aroostook County grew by 0.5 percent from 2002 to 2003, the first population gain since 1991, the Census Bureau said.

The modest gain – 340 people – provides evidence that Aroostook County’s economy is improving after years of struggles capped by the Defense Department’s decision to close Loring Air Force Base.

The census data, released this week, came as a pleasant surprise to state and local economic development officials.

“This is the best news they’ve seen in some time,” Galen Rose, an economist and demographer with the Maine State Planning Office, said Friday from Augusta. “It could mark the bottom there.”

Aroostook, like the rest of Maine’s counties, benefited from migration of people into the state and a relatively stable economy, said Charles Colgan, a professor of public policy and management at the University of Southern Maine’s Muskie School.

Overall, 10,814 people moved to Maine from July 2002 to July 2003, said Colgan. The biggest beneficiaries were York, Cumberland and Kennebec counties, but the trend reached all 16 counties.

In Aroostook County, the economy imploded when the last Air Force jets departed in 1994. Homes came onto the market with few buyers and scores of businesses went under. In Caribou alone, more than 100 businesses closed their doors in the economic disaster that ensued.

State economist Laurie Lachance said some of the factors helping Aroostook have been the success of the Loring Development Authority and the Maine Winter Sports Center, recent host of the World Cup biathlon.

The county’s unemployment rate has dropped from a 12.3 percent peak in the mid-1990s to 5.7 percent last year.

“I think it’s a wonderful example of how a rural region can take hold of the situation and turn it around,” she said.

Bob Clark, executive director of the Northern Maine Development Commission, said there’s still work to be done.

With a population of 73,428, Aroostook County is far from its peak of 106,000 residents in the 1960s. Since then, mechanization in the farming and forestry industries caused jobs to dry up.

But technology is bringing new jobs to the county, he said.

“We’ve lost several hundred jobs in the past year, but we’ve been able to replace them with new business startups,” he said.

One of the newest businesses at the Loring Commerce Centre is Pattison Signs, a Canadian company that makes signs for Toyota dealerships across the country. It is one of many success stories.

“We see reasons to be optimistic,” said Carl Flora, president and CEO of Loring Development Authority in Limestone.

Flora believes many former Aroostook County residents who moved away in search of economic opportunity would return if they could find good jobs.

“We’ve known for a long time that there are people living in other parts of the country who have roots in Aroostook County and are interested in moving back,” he said. “The only thing that’s stopping them is the lack of a job or appropriate economic opportunity.”