The US economy grew by far more than was initially thought between April and June.
The revised figure was inflated from 2.3 percent, as previously announced, to 3.7% to reflect greater corporate investment.
Wall Street reacted well to the news, with the Dow up 1.3 percent an hour after opening. Economists polled by Reuters had expected that second-quarter GDP growth would be revised to a 3.2 percent rate.
Consumer spending figures were also revised, growing at 3.1 percent, rather than the 2.9 percent pace reported last month.