NBER says not clear yet when U.S. recession ended

"Although most indicators have turned up, the committee decided that the determination of the trough date on the basis of current data would be premature," the National Bureau of Economic Research said in a statement.

"Many indicators are quite preliminary at this time and will be revised in coming months," the group said.

The NBER said its business cycle dating committee, a group of economists that pinpoints when recessions begin and end, had met on April 8 to consider whether it had enough data to call the end of the latest slump.

The group looks at a range of indicators, not just gross domestic product, to determine when business cycles begin and end, and is well-known for waiting many months before making its determinations.

However, some committee members have said recently that they believed the recession ended last summer or fall, judging by economic growth, employment and other factors.

Many private economists think the downturn probably ended in June or perhaps a couple of months later. The economy resumed growth in the third quarter of 2009, although employment continued to contract for several more months. Payrolls have recorded only two monthly gains since the recession started -- in November 2009 and March 2010.

The NBER said its committee reaffirmed that the recession began in December 2007.

(Reporting by Emily Kaiser; editing by Patrick Graham)