Economic growth in the United States unexpectedly slowed in the fourth quarter as strong consumer spending resulted in a surge of imports, Reuters reported. Gross domestic product increased at a 2.6 percent annual rate after economists had forecast 3 percent for the final three months of 2017. The new numbers contrast with a 3.2 percent growth rate for the third quarter. Still, consumer spending, which accounts for more than two-thirds of U.S. economic activity, increased at a 3.8 percent rate in the fourth quarter — the quickest pace in three years. Imports grew at a 13.9 percent rate.