In conducting nonresponse follow-up, the bureau has historically faced the twin challenge of (1) collecting quality data (by obtaining complete and accurate information directly from household members) while (2) finishing the operation on schedule, before error rates can increase as people move or have trouble recalling who was living at their homes on Census Day (April 1), as well as keeping subsequent operations on-track. Nonresponse follow-up was scheduled to begin on April 27, 2000, and end 10 weeks later, on July 7, 2000. Local census offices generally finished their nonresponse follow-up workloads ahead of the bureau’s 10-week schedule. As shown in figure 1, of the bureau’s 511 local offices in the 50 states, 463 (91 percent) finished nonresponse follow-up by the end of the eighth week of the operation, consistent with the bureau’s internal stretch goals. Moreover, nine local offices completed their workloads in as little as 5 weeks or less. The timely completion of nonresponse follow-up in 2000 stands in sharp contrast to the bureau’s experience during the 1990 Census. As shown in figure 2, at the end of the 6-week scheduled time frame for nonresponse follow-up during the 1990 Census, the bureau had not completed the operation. In fact, as of two days prior to the scheduled end date, just two local census offices had completed the operation and the bureau had only completed about 72 percent of its 34 million household follow-up workload. It took the bureau a total of 14 weeks to complete the entire operation. By comparison, as noted above, the bureau completed nonresponse follow-up in less than 10 weeks during the 2000 Census. Figure 2 also highlights the drop-off in production that occurs during the later weeks of nonresponse follow-up. According to the bureau, the decline occurs because unresolved cases at the end of nonresponse follow- up are typically the most difficult to reach, either because they are uncooperative or are rarely at home and are unknown to neighbors. To meet our objectives, we used a combination of approaches and methods to examine the conduct of nonresponse follow-up. These included statistical analyses; interviews with key bureau headquarters officials, regional census center officials, and local census office managers and staff; observations of local census offices’ nonresponse follow-up operations; and reviews of relevant documentation. To examine the factors that contributed to the timely completion of nonresponse follow-up, we interviewed local census office managers and other supervisory staff at 60 local census offices we visited across the country. These offices generally faced specific enumeration challenges when nonresponse follow-up began in late April, and were thus prone to operational problems that could affect data quality (see app. I for a complete list of the offices we visited). Specifically, these offices had (1) a larger nonresponse follow-up workload than initially planned; (2) multiple areas that were relatively hard-to-enumerate, such as non-English-speaking groups; and (3) difficulties meeting their enumerator recruiting goals. During these visits, which took place in June and July 2000, we also observed office operations to see how office staff were processing questionnaires; at 12 of these offices we attended enumerator training; and at 31 offices we reviewed key reinterview documents in a given week during nonresponse follow-up. The local census offices we visited represent a mix of urban, suburban, and rural locations. However, because they were judgmentally selected, our findings from these visits cannot be projected to the universe of local census offices. To obtain a broader perspective of the conduct of nonresponse follow-up, we used the results of our survey of a stratified random sample of managers at 250 local census offices. The survey—which asked these managers about the implementation of a number of key field operations— is generalizable to the 511 local census offices located in the 50 states. We obtained responses from managers at 236 local census offices (about a 94 percent overall response rate). All reported percentages are estimates based on the sample and are subject to some sampling error as well as nonsampling error. In general, percentage estimates in this report for the entire sample have confidence intervals ranging from about ± 4 to ± 5 percentage points at the 95 percent confidence interval. In other words, if all managers in our local census office population had been surveyed, the chances are 95 out of 100 that the result obtained would not differ from our sample estimate in the more extreme cases by more than ± 5 percent. To examine whether the pace of nonresponse follow-up was associated with the collection of less complete data, in addition to the efforts described above, we analyzed bureau data on the weekly progress of nonresponse follow-up. Specific measures we analyzed included the time it took local census offices to finish nonresponse follow-up and the proportion of their cases completed by (1) “close-out” interviews, where questionnaires only contain basic information on the status of the housing unit (e.g., whether it was occupied), or (2) “partial” interviews, which contain more information than a close-out interview but are still less than complete. The completeness of the data collected by enumerators is one measure of the quality of nonresponse follow-up, and these two measures were the best indicators of completeness available from the database. We included data from the 511 offices located in the 50 states and controlled for enumeration difficulty using an index measure developed by the bureau. We did not include any outliers that the bureau identified as erroneous (for example, outliers resulting from coding errors). We did our audit work at the local census offices identified in appendix I and their respective regional census centers; bureau headquarters in Suitland, Maryland; and Washington, DC, from March 2000 through September 2001. Our work was done in accordance with generally accepted government auditing standards. We requested comments on a draft of this report from the Secretary of Commerce. On January 10, 2002, the Secretary forwarded the bureau’s written comments on the draft (see app. II) which we address at the end of this report. Key to the bureau’s timely completion of nonresponse follow-up in 2000 was a higher than expected initial mail response rate that decreased the bureau’s follow-up workload. In addition to reducing the staff, time, and money required to complete the census count, the bureau’s past experience and evaluations suggest that the quality of data obtained from questionnaires returned by mail is better than the data collected by enumerators. To help raise the mail response rate, the bureau (1) hired a consortium of private-sector advertising agencies, led by Young & Rubicam, to develop a national, multimedia paid advertising program, and (2) partnered with local governments, community groups, businesses, nongovernmental organizations, and other entities to promote the census on a grassroots basis (we discuss the bureau’s partnership program in more detail in our August 2001 report). The outreach and promotion campaign encouraged people to complete their census questionnaires by conveying the message that census participation helped their communities. The bureau also helped boost the mail response rate by using simplified questionnaires, which was consistent with our past suggestions, and by developing more ways to respond to the census, such as using the Internet. The bureau achieved an initial mail response rate of about 64 percent, which was about 3 percentage points higher than the 61 percent response rate the bureau expected when planning for nonresponse follow-up.This, in turn, resulted in a nonresponse follow-up workload of about 42 million housing units, which was about 4 million fewer housing units than the bureau would have faced under its planning assumption of a 61 percent mail response rate. In addition to surpassing its national response rate goals, the bureau exceeded its own expectations at the local level. Of the 511 local census offices, 378 (74 percent) met or exceeded the bureau's expected response rate. In so doing, these offices reduced their nonresponse follow-up workloads from the expected levels by between 54 and 58,329 housing units. The remaining 133 offices (26 percent) did not meet their expected response rate and the workload at these offices increased from their expected levels by between 279 and 33,402 housing units. The bureau’s success in surpassing its response rate goals was noteworthy given the formidable societal challenges it faced. These challenges included attitudinal factors such as concerns over privacy, and demographic trends such as more complex living arrangements. However, as the bureau plans for the next census in 2010, it faces the difficulty of boosting public participation while keeping costs manageable. As we noted in our December 2001 report, although the bureau achieved similar response rates in 1990 and 2000 (65 percent in 1990 and 64 percent in 2000), the bureau spent far more money on outreach and promotion in 2000: about $3.19 per household in 2000 compared to $0.88 in 1990 (in constant fiscal year 2000 dollars), an increase of 260 percent. Moreover, the societal challenges the bureau encountered in 1990 and 2000 will probably be more complex in 2010, and simply staying on par with the 2000 response rate will likely require an even greater investment of bureau resources. Further, while the mail response rate provides a direct indication of the nonresponse workload, it is an imperfect measure of public cooperation with the census as it is calculated as a percentage of all forms in the mail- back universe from which the bureau received a questionnaire. Because the mail-back universe includes housing units that the bureau determines are nonexistent or vacant during nonresponse follow-up, a more precise measure of public cooperation is the mail return rate, which excludes vacant and nonexistent housing units. According to preliminary bureau data, the mail return rate for the 2000 Census was 72 percent, a decline of 2 percentage points from the 74 percent mail return rate the bureau achieved in 1990. As shown in figure 3, in 2000, the bureau reduced, but did not reverse, the steady decline in public cooperation that has occurred with each decennial census since the bureau first initiated a national mail- out/mail-back approach in 1970.