The nation's economy grew at a 2.6 percent annual rate in the summer quarter, a slight upward revision from an estimate a month ago, the government reported Wednesday.

The change from a 2.5 percent rise in the gross domestic product in the third quarter still means economic growth isn't strong enough to cut unemployment or prevent prices from stagnating. Economists generally regard at least 3.0 percent to 3.5 percent growth as needed for a strong economy.

The latest figure from the Commerce Department highlights why the Federal Reserve plans to keep pumping money into financial markets. The Fed's commitment to buy an additional $600 billion in Treasury notes, combined with additional government stimulus, may help accelerate household spending.

The gross domestic product is the broadest gauge of the nation's economic performance, measuring the value of all goods and services produced in the United States.

The Commerce report also showed that consumer costs for goods and services, excluding food and fuel, climbed in the third quarter at the slowest pace since records began in 1959.

The lack of "inflation does remain the biggest downside risk to the U.S. economy" and growth "is not enough to move unemployment meaningfully," said Guy LeBas, chief fixed-income strategist at Janney Montgomery Scott L.L.C., of Philadelphia.

Thursday's GDP report was the third and final for the quarter. The world's largest economy grew at an annual rate of 1.7 percent pace in the previous three months.

In the past two weeks, economists have boosted forecasts for fourth-quarter growth after the government reported better-than-projected retail sales for November and the Obama administration reached a compromise with congressional Republicans to extend tax cuts put in place by former President George W. Bush.

The economy has not been growing fast enough to cut the unemployment rate, currently at 9.8 percent and a concern of Fed policymakers. The central bank's Open Market Committee on Dec. 14 repeated its pledge to leave the benchmark interest rate low for an "extended period" and retained a Treasury-purchase program through June.

Inflation is also lower than the policymakers' long-term forecast. The Fed's preferred price gauge, which is tied to consumer spending and strips out food and energy costs, rose at a record-low 0.5 percent annual pace, Wednesday's report showed.

It also showed that consumer spending rose at a 2.4 percent pace last quarter, the fastest since the start of 2007, though less than the 2.8 percent estimated last month. The change reflected less spending on health-care and financial services.

Corporate profits increased 1.6 percent from the previous three months, revised from the 2.8 percent gain estimated in November, Wednesday's report showed. They were up 26 percent from the same period a year earlier.