Boston Properties (BXP), the largest office real estate investment trust in the country, reported fourth-quarter funds from operations that almost doubled the prior year.

Funds from operations gauge a property firm’s ability to generate dollars. The company recorded $179.3 million in FFO in the fourth quarter compared with $89.9 million a year earlier. Debt redemptions in the fourth quarter of 2010 cost the company about $81.7 million in early payment charges, according to a statement.

As of Dec. 31, the landlord’s portfolio consisted of 153 properties, comprised primarily of Class A office space, one hotel, three residential properties and three retail properties. Those total approximately 42.2 million square feet, including seven properties under construction totaling 2.6 million square feet. The company has structured parking for vehicles containing approximately 15.1 million square feet.

BXP depends greatly on the rents generated from its office properties in Boston, Washington, D.C., New York and San Francisco. As of Dec. 31, the overall percentage of leased space for the 143 properties in service, minus the two in-service residential properties and the hotel, was 91.3 percent, the company said.

Significant events during the fourth quarter included the company using available cash to repay the mortgage loan collateralized by its Reservoir Place property in Waltham, totaling $50 million.

On Nov. 16, the company completed and fully placed in-service the office component of its Atlantic Wharf development project in Boston. The office component is comprised of approximately 798,000 net rentable square feet and is currently 93 percent leased. In addition, the company terminated the construction loan facility collateralized by the office component of the Atlantic Wharf project totaling $192.5 million.