The latest employment report out of the Bureau of Labor Statistics provided a case study in the difficulty of using the headline numbers to assess the jobs market and peg fiscal and monetary policy to the numbers.

The overall unemployment rate fell 3 points to 6.7 percent in December, but the BLS said two-thirds of the decline was from a decline in labor force participation, which fell to 62.8 percent, the lowest level since 1978.

The more detailed numbers also showed sharply different jobs fortunes across regions and industries.

Retail trade grew by 55,000 jobs, but manufacturing, which has seen signals of improving demand and production in recent months, added only 9,000 jobs in December. That industry added only half the jobs in all of 2013 that factories added the year before.

There were some positive indications behind the headline numbers — with upward revisions for October and November — private employers averaged 177,000 new jobs over the last three months of the year. But the last numbers of 2013 will set the tone for a debate on policies for a Congress that is focused, one way or another, on employment.

House Majority Leader Eric Cantor, R-Va., derided the “lowest level of job creation since January 2011” on the floor Friday. “That doesn’t focus well on the track record” of the administration, he said, arguing for enactment of a series of GOP fiscal priorities.