Orleans and other affected Gulf Coast areas offer a striking example of the way in which long-form-sample data from a census could become irrelevant. Even though increasingly out of date, the 2000 long-form-sample data may have approximated the characteristics of the population in these areas reasonably well through the summer of 2005. However, after the hurricanes hit and so many people fled the area, moved into temporary housing, lost their jobs, or experienced other major changes in their living situations, the 2000 long-form-sample data no longer came close to approximating the numbers and characteristics of the remaining residents. In contrast, in June 2006 the Census Bureau was able to issue a special product from the 2005 ACS for these areas, providing separate estimates for the period January-August 2005 and the period September-December 2005.3
Not only were the long-form-sample products delayed because of the priority given to completing the head count, but also in 2000, even more than in prior censuses, there was not a dedicated effort to collecting long-form information during nonresponse follow-up. Furthermore, in 2000 there was no operation to follow up households that mailed back incomplete long-form questionnaires. Consequently, nonresponse rates were very high in 2000 for many long-form items, particularly those obtained in follow-up operations by temporary, minimally trained field staff. They were high absolutely and in comparison with the 2000 ACS test survey (known as the Census 2000 Supplementary Survey or C2SS), for which the Census Bureau used permanent, highly trained interviewers in nonresponse follow-up (Schneider, 2004:Appendix Tables 1, 2). Measurement error may also have been greater for long-form-type information collected as part of the census than is the case for the ACS.
The paired strategy limited the opportunities to revise the questionnaire to respond to emerging data needs or to improve response quality. Although it is unclear how often ACS questions can be revised, the strategy of obtaining long-form-type information in the continuous measurement design of the ACS should allow for additions to the questionnaire to address current issues of interest more frequently than once every 10 years.
An important consideration for the Census Bureau is that the infrastructure needed to administer a short-form census can be much more efficient than the infrastructure needed to administer both the short form and the long form. Indeed, the current design for carrying out the short-form-only census in 2010 envisions the use of handheld computing devices
Available at http://www.census.gov/acs/www/Products/Profiles/gulf_coast/index.htm. The special ACS estimates were not without problems—the hurricanes disrupted postal service delivery, dislocated the interviewer workforce, and made it difficult to complete interviews from sample households. Moreover, post-hurricane population and housing unit estimates were not available to use as controls for the ACS post-hurricane estimates, so no controls were used.