A worker removes bolts from a concrete form at Doty & Sons Concrete Products in Sycamore, Illinois.

The U.S. economy grew at its fastest pace in 2-1/2 years in the second quarter and activity was broad-based, in a bullish signal for the remainder of the year.

The Commerce Department on Friday raised its estimate of gross domestic product (GDP) to show the economy expanded at a 4.6 percent annual rate. The best performance since the fourth quarter of 2011 reflected a faster pace of business spending and sturdier export growth than previously estimated.