In a sign that the economy may be picking up, the gross domestic product increased at an annual rate of 2.2% in the third quarter, according to a third estimate released today by the Commerce Department.

That's down from the department's second estimate of 2.8% and first one of 3.5%, but an improvement over the second quarter, when it declined 0.7%.

From July through September, real gross domestic purchases-purchases by Americans of goods and services wherever they were produced-increased 3%. By contrast, there was a 2.3% decline in the second quarter. The department cited a rise in personal, business and government spending and exports as the reasons for the improvement.

Exports increased 17.8%, while there had been a 4.1% drop in the second quarter.

Imports rose 21.3%, an increase from the second estimate of 20.8% and the preliminary estimate of 16.4%. In the second quarter, imports dropped 14.7%.

Consumers paid more for some products. The price index for gross domestic purchases increased 1.3%. During the second quarter, the index increased 0.5%.

Personal consumption expenditures increased 2.8%, compared to the second quarter when expenditures declined 0.9%.

Residential fixed investment, which includes housing, increased 18.9%. By contrast, in the second quarter that investment fell 23.4%.