Gross domestic product expanded at a 3.7 percent annual pace instead of the 2.3 percent rate reported last month, the Commerce Department said on Thursday in its second GDP estimate.
The GDP report, which was released in the wake of a global stock market sell-off, should assure investors and cautious Fed officials that the United States was in good shape to weather the growing strains in the world economy.
Concerns over slowing economic growth in China sent global equity markets into a tailspin last week, raising doubts that the U.S. central bank would raise its short-term interest rate next month.
On Wednesday, New York Fed President William Dudley said that prospects of a September lift-off in the central bank's key lending rate "seems less compelling to me than it was a few weeks ago."
Prices for U.S. government debt fell after the GDP data, while U.S. stock index futures held on to gains. The dollar was stronger against a basket of currencies.
The upward revisions to second-quarter growth also reflected the accumulation of $121.1 billion worth of inventories, $11.1 billion more than previously estimated. That meant inventories contributed 0.22 percentage point to GDP instead of subtracting 0.08 percentage point as reported last month.
While the huge inventory build will likely weigh on growth in the third quarter, the blow could be softened by rebounding business investment in capital goods.
Economists polled by Reuters had expected that second-quarter GDP growth would be revised to a 3.2 percent rate.
The economy grew at a 0.6 percent rate in the first quarter. Output expanded 2.2 percent in the first half of the year compared to growth of 1.9 percent during the same period in 2014.
Strong domestic demand
Underscoring the solid economic fundamentals, a measure of private domestic demand that excludes trade, inventories and government expenditures increased at a 3.3 percent rate in the second quarter, instead of the previously reported 2.5 percent pace.
Consumer spending, which accounts for more than two-thirds of U.S. economic activity, grew at a 3.1 percent rate, rather than the 2.9 percent pace reported last month. Consumer spending got off to a brisk start in the third quarter, with retail sales rising solidly in July.
A strong labor market, cheaper gasoline and relatively higher house prices are boosting household wealth, helping to support consumer spending.
The employment picture was further brightened on Thursday by a separate report from the Labor Department showing initial claims for state unemployment benefits slipped 6,000 to a seasonally adjusted 271,000 for the week ended Aug. 22.
It was the 25th straight week that claims remained below the 300,000 threshold, which is usually associated with a strengthening labor market.
The Commerce Department said investment in nonresidential structures was revised to show an increase of 3.1 percent, reflecting stronger spending on commercial and healthcare construction. It was previously reported to have contracted at a 1.6 percent pace.
Spending on residential construction was raised to a 7.8 percent pace from a 6.6 percent rate. Business spending on equipment was not as weak as initially thought.
The energy sector continued to weigh on growth as it struggles with the lingering effects of deep spending cuts by oil-field companies like Schlumberger and Halliburton in the aftermath of a more than 60 percent plunge in crude oil prices since last year.
Spending on mining exploration, wells and shafts plunged at a 68.3 percent rate in the second quarter, the largest decline since the second quarter of 1986.
The trade deficit was smaller than previously reported, adding 0.23 percentage point to GDP growth.
The GDP report also showed after-tax corporate profits rebounded 1.3 percent in the second quarter after declining 7.9 percent in the first quarter. A strong dollar has constrained the profits of multinational corporations.
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