Figures show that US workers' productivity grew at a slower pace than initially estimated during the first three months of this year as the economy just inched ahead.
The figures drove up labour costs and appeared to support the Federal Reserve's belief that inflation is a concern.
The Labor Department reported that non-farm productivity, a measure of how much any given worker can produce in an hour, advanced at an annual rate of 1% during the first quarter of this year, driving up unit labour costs by 1.8%.
The Labor Department's earlier estimate for first-quarter productivity showed it rising at a seasonally adjusted annual rate of 1.7% and unit labour costs increasing 0.6%.
Meanwhile, the White House has trimmed its US economic growth forecast for 2007 to 2.3%, saying the slow pace of activity early this year would pick up as the year progresses.
The bi-annual forecast was cut from 2.9% six months earlier, and is roughly in line with the outlook of most private economists in light of a sharp slowdown in the first quarter of the year.
