The number of unemployed U.S. workers seeking jobless assistance fell last week to the lowest level in nearly four years, a new sign the labor market is improving for the world's largest economy.

The government's Labor Department reported Thursday that 359,000 jobless workers made new claims for financial aid, down 5,000 from the week before. It was the lowest total since April 2008, just before millions of workers started losing their jobs in the country's worst economic downturn in seven decades.

The government's latest jobless claims report revised some of its weekly totals to higher levels over the last several years. But the downward trend over the last several months was still evident, with employers boosting their hiring as the U.S. economy improves.

U.S. businesses added nearly three-quarters of a million new jobs in the last three months. But almost 13 million workers remain unemployed and the country's jobless rate has been pegged at 8.3 percent for the last two months. The unemployment figure is still elevated by U.S. standards, with about 5 percent more normal.

In a separate report, the government confirmed an earlier projection that the U.S. economy advanced by 3 percent in the last three months of 2011. Now, however, economists are projecting that the American economy has slowed to half that pace in the early months of this year.