however, promises to allow the ACS to develop in ways that, while not clear today, will allow this new survey to become much more powerful than the long-form sample could ever be. We urge users to take a long view of the ACS and be open to new uses that were not possible with the long-form sample but that the continuously updated ACS data can support.

The Census Bureau, for its part, needs to provide as much guidance and training as possible to users to help them maximize the upside and minimize the downside of working with this complex data set. As discussed in Chapter 7, the Census Bureau should proactively identify ways to assist the occasional user who will not be in a position to master the ins and outs of the ACS data—for example, by highlighting estimates that meet reasonable standards for precision. The Census Bureau should also support an ongoing education and outreach program for users who plan to work extensively with ACS data, including the staffs of state data centers and other groups whose mission is to assist the broad user community. As discussed in Chapter 4, the Census Bureau should consider the development of new data products that would help many users, such as 3-year period estimates for statistical areas that are larger than census tracts and smaller than public use microdata areas (PUMAs).


Federal government agencies have historically used data from the long-form sample for a wide range of purposes. For at least the past two censuses, the Census Bureau and the U.S. Office of Management and Budget (OMB) have required that each item on the census short and long forms be justified as serving a federal agency need. For the long-form sample, each item had to be needed for federal government use for small areas, often as small as census tracts. Uses were classified into three categories: (1) mandated—that is, the use of census data was specified in legislation; (2) required—that is, data were required by legislation and, although the census was not named as the source, it was the only or the historical source of data; and (3) programmatic—that is, the census data were used for agency program planning, implementation, or evaluation or to provide legal evidence. The same general criteria are being applied with the ACS, although congressional oversight committees have indicated that it is not mandatory to pass legislation in order to add a question to the ACS.1 It should be noted that where laws or regulations specify the use of census long-form-sample estimates, changes in legislation may be required to permit the use of ACS estimates instead.


Personal communication, Lynda T. Carlson, Director, Division of Science Resources Statistics, National Science Foundation.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001

Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement