BOSTON (AP) — A company that's leading efforts to computerize health care records nationwide is promising to add 1,900 jobs in Massachusetts in an exchange for a state tax break.

The agreement with athenahealth Inc. is the biggest economic development deal reached with Massachusetts in years, The Boston Globe reported Tuesday.

Athenahealth already has 1,100 employees at its Watertown headquarters, where it plans to add the new jobs.

The director of the Massachusetts Office of Business Development, James Ermilio, said the deal is important because of the new jobs it offers and because it can anchor a key growth sector in the Massachusetts economy. The state's unemployment rate rose to 6.6 percent last month.

"To find a company like athenahealth that is willing to grow here is a great story," Ermilio said.

Under the tentative agreement, athenahealth's workforce in Watertown will nearly triple by 2022 in exchange for $9.5 million in state tax credits. To make room for the new employees, athenahealth recently agreed to buy a Watertown office complex from Harvard University for nearly $169 million.

The tax break works out to about $5,000 per job, which is less than other incentives the state has awarded. For instance, in 2010, the state and the City of Boston combined to offer insurance giant Liberty Mutual $46.5 million in tax breaks, or $77,500 per job, to help it build a skyscraper.

The athenahealth deal includes some of the highest job creation numbers promised under any deal done under the state's two decades old incentive program. But the companies haven't always delivered the jobs envisioned, and Greg LeRoy of Good Jobs First, a Washington group that tracks development incentives, questioned whether the tax incentives are truly needed to attract jobs.

"This sounds like a case where a company is getting paid for what it was doing anyway," he told the Globe.