The White House on Wednesday lowered its forecast for economic growth this year even as it slightly upgraded its outlook for unemployment.

Under the administration's new forecast, gross domestic product, or GDP, will grow by 2.3 percent as measured from the fourth quarter of last year to the fourth quarter of this year. That's down from a previous projection of 2.9 percent.

The main reason for the downgrade: The first three months of 2007 got off to an extremely weak start. Economic growth skidded to nearly a halt, increasing at a rate of just 0.6 percent, the worst showing in more than four years.

Federal Reserve Chairman Ben Bernanke, the administration and private economists expect the economy will rebound in the months ahead. The one wild card, though, is whether the nearly year-long housing slump — which has been a damper on overall economic activity — gets worse.

The economy grew by 3.1 percent in 2006. The persistance of the housing slump is the main force behind the economy's projected loss of momentum this year.

The White House, however, expects the economy will regain speed and grow by 3.1 percent — a solid performance — in 2008 and 2009. Those forecasts are unchanged from previous estimates.

Gross domestic product measures the value of all goods and services produced within the United States. It is the best barometer of the country's economic fitness.

Meanwhile, the nation's unemployment rate, which averaged 4.6 percent last year, a six-year low, is expected to dip to 4.5 percent this year under the administration's new forecast. That is slightly better than its old forecast that the unemployment rate would hold steady at 4.6 percent.

Next year, the administration predicts the unemployment rate will edge up to 4.7 percent. Still that's also a bit better than the old projection of a 4.8 percent jobless rate.

The employment climate has remained healthy even as the economy has endured a sluggish spell. That's because troubles have mostly been contained in the ailing housing and the struggling automotive sectors and have not spread widely, affecting other types of employers.

On the inflation front, surging prices for gasoline and other energy prices prompted the administration to raise its inflation forecast for this year. The White House now expects consumer prices to rise by 3.2 percent this year. That's higher than the 2.6 percent increase previously projected.

However, inflation should settle down after that. The administration expects consumer prices to rise by 2.5 percent in 2008 and edge down to 2.4 percent in 2009.