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WASHINGTON, Jan 5 (Reuters) - U.S. nonfarm payrolls likely increased by 175,000 in December, according to a Reuters poll, instead of the 140,000 expected before an independent report on Wednesday showed a record jump in private jobs last month.
ADP Employer Services, a payrolls processing company, said private-sector employers added 297,000 jobs in December, the biggest rise on records dating to 2000 and up from November's gain of 92,000.
The gain, nearly triple the 100,000 expected in a Reuters poll of economists, prompted some to revise up their forecasts for the government's more comprehensive payroll count due on Friday, arguing that the increase shown in the ADP report was just too large to ignore. They still acknowledged the ADP's poor record at predicting nonfarm payrolls, however.
Economists kept their median U.S. unemployment rate forecast for December at 9.7 percent.
"We have not been particularly fond of the ADP data over the past couple of years because of significant forecast misses," economists wrote at Deutsche Bank in New York, but added they could not "fully ignore the latest ADP figures."
Others cautioned against reading too much into the strength shown in the ADP report, saying the data could have been distorted by seasonal factors. They noted that workers tended to remain on ADP reports until December, regardless of their employment status.
"This results in a large reduction in non-seasonally adjusted payrolls in December," said Daniel Silver, an economist at JPMorgan in New York.
"With fewer firings this year than in recent years, the 'purge' may have been less than the seasonal factors expected which would have caused a 'surge' in the seasonally adjusted data for December."
Silver said the so-called "purge" effect was absent from the government payrolls data.
Economists at Goldman Sachs shared similar views, saying "it's possible some of today's improvement could be the result of this data quirk rather than genuine acceleration." (Polling by Bangalore Polling Unit; Writing by Lucia Mutikani, Editing by James Dalgleish)