important purposes, such as providing factors for fund allocation formulas, controls for other household surveys, and denominators for vital rates. Information from the ACS on place of birth, citizenship, and year of immigration is already used to generate estimates of net migration from abroad for the population estimates program, and the Census Bureau is interested in examining other components of the estimates that might benefit from ACS information. For example, ACS estimates might supplement IRS tax records to estimate internal migration at the county level and perhaps for smaller geographies.
The ACS could also possibly improve the population estimates and its own coverage of population and housing through linkages with the Census Bureau’s E-StARS program (see Section 4-A.4). The E-StARS Master Address Auxiliary File could be used to improve the MAF, which would in turn improve the ACS coverage of housing units. (At present, the MAF provides input to E-StARS, but there is no feedback loop back to the MAF.) Going a next step, ACS estimates of occupancy rates and persons per household could possibly be used with an improved MAF count to generate an alternative set of population estimates to compare with the estimates that are produced from the current component method (see Section 5-C). Yet another approach is to use E-StARS to provide population controls for subcounty areas within the framework of the existing population estimates. The Census Bureau has begun work along these lines, which should be pursued.
Critical to making progress toward improved population estimates is for the Census Bureau to design and conduct an extensive evaluation program of alternative estimation methods and data sources in conjunction with the 2010 census. In planning and evaluating its research, the Census Bureau should involve knowledgeable users and producers of population estimates, such as the members of the Federal State Cooperative Program for Population Estimates.
Most items on the ACS questionnaire are covered in other household surveys, often in much more detail. For example, as noted in Section 7-D.1 above, the monthly CPS, which provides the nation’s official measure of unemployment, includes additional questions about work status beyond those used in the ACS to determine each respondent’s labor force situation. Other surveys that overlap with the ACS include the American Housing Survey, the CPS Annual Social and Economic Supplement, the Survey of Income and Program Participation, the National Health Interview Survey, and the National Household Travel Survey. These other surveys not only obtain extensive information about their primary topic, but also typically include a large number of additional variables for use in analysis. However, they rarely provide state, or substate, estimates.