The nation's labor unions saw another sharp decline in membership last year even as the economic recovery began and job losses slowed.

The Bureau of Labor Statistics says unions lost 612,000 members in 2010. That drops the unionized share of the work force to 11.9 percent from 12.3 percent in 2009.

Union membership in the private sector fell from 7.2 percent to 6.9 percent, a low point not seen since the infancy of the labor movement in the 1930s. The steepest decline was among construction workers.

Public employment unions saw a 1.2 percent decline, as state and local governments cut jobs. Those unions could see further declines this year as states eliminate more government jobs in an effort to balance budgets.