"In spite of this data adjustment, our assessment of the fundamentals of campaign progress has not changed, " Ms Stattel went on.

BBC: Nato admits 'error' in claim of fall in Taliban attacks

But the forecasting firm Macroeconomic Advisers, which prepares the report with ADP, warned Wednesday that its estimate of December job growth might have been stronger than merited because of seasonal-adjustment problems specific to the ADP data set.

WSJ: What's Behind the Jobs Report?