Comparison between the Demographic Composition of Matched IRS Exemptions and 2010 Census Household Population Counts

Joseph Bowman, U.S. Census Bureau
Esther R. Miller, U.S. Census Bureau

The U.S. Census Bureau’s Population Division develops population estimates using a component of population change method. The domestic migration component is indirectly measured by matching two consecutive years of IRS tax return exemptions. Implicit is the assumption that people who do not file taxes migrate at the same rate as tax filers and their associated exemptions. However, the tax filing population may or may not be representative of the population as a whole. This paper provides a comparison of matched IRS exemptions to the enumeration of the United States population in Census 2010. To do this we calculate coverage rates. Coverage rates are the percent at which the matched IRS universe covers the Census 2010 household population counts (i.e., the number of matched IRS exemptions divided by census household population counts). We examine differences in coverage rates by subnational geography and demographic characteristics.