SHADAC prepared this working paper for the Census Bureau to describe a revised data imputation technique for health insurance estimates from the Current Population Survey's Annual Social and Economic Supplement (CPS ASEC). 

This paper was originally released in September 2011 and revised in December 2011. The revision incorporates improved standard error estimates and an analysis on selected sub-groups.

In an experimental version of the 2009 CPS ASEC, the change to the imputation routine and a simultaneous correction to the coding of directly purchased coverage increased the percent of people with health insurance coverage by about 0.5 percentage points (1.5 million people), primarily through an increase in private coverage. The Census Bureau implemented the new method with the 2011 CPS ASEC (reflecting calendar year 2010) and retroactively applied the new routine for the 2000 to 2010 CPS ASECs.

In addition to the new allocation procedures, the new data files reflect all data processing adjustments that have occurred since 2000. The data were released as supplementary files available from the Census Bureau’s health insurance web page. 

These new data will also be available in fall 2011 from SHADAC’s Data Center and  Minnesota Population Center’s Integrated Public Use Microdata Series (IPUMS).

The research that led to these imputation changes was conducted by SHADAC researchers, led by Mike Davern.  Results are published in the 2007 Health Services Research article, "Are the Current Population Survey Uninsurance Estimates Too High? An Examination of the Imputation Process."