Effective with data for January 2012, updated population estimates which reflect the results of Census 2010 have been used in the household survey. Population estimates for the household survey are developed by the U.S. Census Bureau. Each year, the Census Bureau updates the estimates to reflect new information and assumptions about the growth of the population during the decade. The change in
population reflected in the new estimates results from the introduction of the Census 2010 count as the new population base, adjustments for net international migration, updated vital statistics and other
information, and some methodological changes in the estimation process.
The vast majority of the population change, however, is due to the change in base population from Census 2000 to Census 2010.
In accordance with usual practice, BLS will not revise the official household survey estimates for December 2011 and earlier months. To show the impact of the population adjustment, however,
differences in selected December 2011 labor force series based on the old and new population estimates are shown in table B.
The adjustment increased the estimated size of the civilian noninstitutional population in December by 1,510,000, the civilian labor force by 258,000, employment by 216,000, unemployment by 42,000, and persons not in the labor force by 1,252,000. Although the total unemployment rate was unaffected, the labor force participation rate and the employment-population ratio were each reduced by 0.3 percentage point. This was because the population increase was primarily among persons 55 and older and, to a lesser degree, persons 16 to 24 years of age. Both these age groups have lower levels of labor force participation than the general population.
