2010 Census: The Bureau's Plans for Reducing the Undercount Show Promise, but Key Uncertainties Remain
Released: 2008-09-23T00:00:00

Letter

Background

The Bureau puts forth tremendous effort to conduct an accurate count of the nation’s population. However, some degree of coverage error in the form of persons missed or counted more than once is inevitable. Two types of errors that can affect the accuracy of the enumeration are the omission of persons who should have been counted and erroneous enumerations of persons who should not have been counted.

Historically, undercounts have plagued the census, although, according to the Bureau, they have generally diminished since 1940. For the 2000 Census, for the first time in its history, the Bureau reported a slight net overcount of approximately 0.5 percent or about 1.3 million people. However, as shown in figure 1, coverage errors were not evenly distributed through the population. For example, there was an overcount of non-Hispanic Whites, and an undercount of non-Hispanic Blacks. Nevertheless, figure 1 also shows the strides the Bureau made in reducing the undercount in the 2000 Census compared to 1990.

Importantly, the national net overcount of about 0.5 percent does not mean that 99.5 percent of the population was counted correctly in 2000. In fact, the number of persons who were counted twice in the census was partially offset by the number of persons who were missed by the census. We have long maintained that the sum of these numbers—known as gross error (rather than the difference between the two numbers or net error)— provides a more comprehensive measure of total error in the census.

Participation in the census, as measured by the mail return rate, also affects the accuracy of census data. The Bureau calculates mail return rates as the percentage of questionnaires the Bureau receives from occupied housing units in the mail-back universe. Although individuals who fail to mail back their census forms might be counted by an enumerator during a subsequent operation called nonresponse follow-up, high mail return rates are critical to quality data. A Bureau evaluation of the 2000 Census found that responses from mail returns tend to be more accurate than those obtained during nonresponse follow-up.

Historically, return rates have declined. According to the Bureau, in 1970, for example, the overall mail return rate was 87.0 percent; in 1980, 81.3 percent; and in 1990 and 2000, 74.1 percent. Importantly, as shown in figure 2, during the 2000 Census, differentials existed in the mail return rates of different demographic groups. For example, Whites had a higher mail return rate (77.5 percent) than the rate for all groups (74.1 percent), while nearly every other demographic group had lower return rates than the overall mail return rate. The lowest mail return rates were those of Pacific Islanders (54.6 percent) and those of two or more races (57.7 percent). Maintaining or increasing mail return rates, especially minority return rates, represents an important opportunity for the Bureau to improve the quality of census data.

A Number of Census Operations Are Aimed at Improving Coverage

In designing the 2010 Census, the Bureau recognized the importance of including a number of operations aimed at improving coverage and reducing the differential undercount. Three such efforts that I will highlight in my remarks today are (1) a complete and accurate address list, (2) an Integrated Communications Campaign to increase awareness and encourage participation, and (3) special enumeration programs targeted toward historically undercounted populations. These activities, along with a number of others planned for 2010, will position the Bureau to reduce the undercount. At the same time, each faces particular challenges and uncertainties that I will describe later in my statement.

Building a Complete and Accurate Address List

The foundation of a successful census is a complete and accurate address list and the maps that go with it. The Bureau’s Master Address File (MAF) is the inventory of the nation’s roughly 133.7 million housing units. In so far as it is used to deliver questionnaires as well as to organize the collection and tabulation of the data, the MAF serves as the basic control for the census.

The Bureau develops its address list and maps over the course of the decade using a series of operations that sometimes overlap to increase the accuracy of the list of all housing units are included. These operations include partnerships with the U.S. Postal Service and other federal agencies; state, local, and tribal governments; and local planning organizations.

Three operations that can help include the hard-to-count are the Bureau’s Local Update of Census Addresses (LUCA) program, address canvassing, and Group Quarters Validation.

Local Update of Census Addresses

The LUCA program gives state, local, and tribal governments the opportunity to review and update the list of addresses and maps that the Bureau will use to deliver questionnaires within those communities. According to Bureau officials, LUCA helps identify hard-to-count populations and “hidden” housing units such as converted basements because local governments might know where such dwellings exist and have access to local data and records. In October 2008, the Bureau is scheduled to complete its reviews of participants’ LUCA submissions and update the MAF and a related geographic database used for maps.

Address Canvassing

In the address canvassing operation, thousands of temporary Bureau employees known as listers verify the addresses of all housing units— including those addresses provided by localities in LUCA—by going door to door across the country. As part of this effort, listers add addresses that might not be in the Bureau’s database. To help find hidden housing units it might otherwise miss, listers ask if there is more than one residence at a particular address, or to look for clues such as an outbuilding or two mailboxes or utility meters that could indicate additional households. Indeed, as shown in the picture on the left in figure 3, someone could be living in what appears to be a storage shed. Likewise, in the picture on the right, what appears to be a small, single-family house could contain another apartment as suggested by its two doorbells. such as single-family houses, apartments and mobile homes, the 2000 decennial enumerated over seven million people living in group situations such as college dormitories, nursing homes, migrant labor camps, prisons, and group homes, collectively known as “group quarters”. Some group quarters, such as seasonal and migrant labor camps, can be difficult to locate because they are sometimes fenced-in or in remote locations away from main roads. The Bureau encountered a number of problems when enumerating group quarters during the 2000 Census. For example, in 2000, communities reported instances where students in college dormitories were counted twice and prison inmates were counted in the wrong county. Additionally, group homes are sometimes difficult for census workers to spot because, as shown in figure 4, they can look the same as conventional housing units.

Since 1970, the Bureau has conducted a separate operation to enumerate the group quarters population. For 2010, the Bureau has plans to conduct Group Quarters Validation to validate the addresses found in the Address Canvassing operation and collect information about the type of group quarters.

Encouraging Participation through the Integrated Communications Campaign

The Bureau’s Integrated Communications Campaign is designed to increase the mail response rate, improve cooperation with enumerators, enhance the overall accuracy of the census, and reduce the differential undercount. The Bureau estimates it will spend $410 million on the Integrated Communications Campaign for the 2010 Census.

In September 2007, the Bureau awarded its communications contract to DraftFCB, a communications firm hired to orchestrate a number of communications activities for the 2010 Census. DraftFCB’s approach includes a specific focus on undercounted populations. As one example, the contractor worked with the Bureau to segment the nation’s population into distinct “clusters” using socioeconomic, demographic, and other data from the 2000 Census that are correlated with a person’s likelihood to participate in the census. Each cluster was given a hard-to-count score and the Bureau’s communications efforts are to be targeted to those clusters with the highest scores. The four clusters with the highest hard- to-count scores made up 14 percent of the nation’s occupied housing units based on data from the 2000 Census, and included the following demographic characteristics: renters, immigrants, non-English speakers, persons without higher education, persons receiving public assistance, and persons who are unemployed.

Targeting the Bureau’s communications campaign to hard-to-count populations will help the Bureau use its resources more effectively. This will be important because in constant 2010 dollars, the Bureau will be spending less on communications for the 2010 Census ($410 million) compared to the 2000 Census ($480 million).

The campaign strategy will be based on the theme “It’s In Our Hands”. According to the Bureau, this approach reflects a marketplace trend where communications are becoming more two-way or participatory, and can be seen, for example, in people creating their own content on the World Wide Web. The goal of the strategy is to encourage personal ownership and involvement that spreads the word about the census. The Bureau believes this approach will be more effective than if the message came from the government talking to the public. Further, the generic theme will be tailored to specific groups. For example, outreach targeted to families might carry the message, “The education of our children. . .It’s in our hands,” while the economically disadvantaged might receive “The power to matter. . .It’s in our hands.”

The communications campaign consists of (1) paid media including national, local, outdoor, and online advertisements; (2) earned media and public relations such as news releases, media briefings, special events, podcasts, and blogs; (3) Census in Schools, a program designed to reach parents and guardians through their school age children, and (4) partnerships with key national and local grassroots organizations that have strong connections to their communities.

Although the effects of the Bureau’s communication efforts are difficult to measure, the Bureau reported some positive results from its 2000 Census marketing efforts with respect to raising awareness. For example, four population groups—non-Hispanic Blacks, non-Hispanic Whites, Asians, and Native Hawaiians indicated they were more likely to return the census form after the 2000 Census Partnership and Marketing Program than before its onset. However, the Bureau also reported that the 2000 Census Partnership and Marketing Program had mixed success in favorably impacting actual participation in the census.

Of the various campaign components, the Census in Schools and partnership programs are specifically aimed at hard-to-count populations. The Census in Schools program provides curriculum and teaching materials that introduce students to the purpose and importance of the census as well as census activities and products. The program is also designed to engage students to encourage their parents to complete and return their census questionnaires.

According to Bureau officials, although the Census in Schools program is not as extensive as the one conducted in the last decennial, they made a number of changes based on lessons learned from the 2000 Census. For example, the program will spend less on printing and base their 2010 Census materials on materials used for the 2000 Census rather than create new materials from scratch. Moreover, similar to 2000, the Bureau is not reaching out to all schools but instead plans to target schools with large hard-to-count populations. Lower grades will be targeted as well, as Bureau officials believe their message has more traction with younger students.

Under the partnership program, the Bureau plans to hire specialists to collaborate with local individuals and organizations, leveraging their knowledge and expertise to increase participation in the census within their communities. Partnership specialists are to be trained in, and help implement, various aspects of the census, as well as to reach out to key government and community leaders and gain commitments from community organizations to help the Bureau execute the enumeration.

Reaching Out to Undercounted Populations Using Special Enumeration Activities

The Bureau operates a wide range of special enumeration programs—such as Be Counted, Questionnaire Assistance Centers (QAC) and Service- Based Enumeration—that target hard-to-count populations. Other activities, such as offering in-language questionnaires and replacement questionnaire mailings for nonresponding households, can help increase participation in non-English speaking populations as well as residents in areas with historically low responses rates.

Be Counted program and Questionnaire Assistance Centers

The Bureau developed the Be Counted program to enumerate people who believe they did not receive a census questionnaire, or were otherwise not included in the census. The Be Counted form is a questionnaire intended to be placed in public locations such as stores, libraries, and other places where people congregate (see figure 5). QAC staff help people complete their Be Counted forms as well as other census forms. Census officials reported that approximately 560,000 people were enumerated through the Be Counted program in 2000 that might have otherwise been missed. Additionally, a Bureau evaluation found that Be Counted forms were more likely to include members of minority groups and children—two traditionally undercounted populations—when compared to the traditional mail forms. Plans for the 2010 decennial include 30,000 QAC sites (a 25 percent increase over the 2000 Census) and 40,000 Be Counted sites, which are oftentimes co-located with QACs but can be stand-alone sites. Partnership specialists are to help determine the location of the sites, which are to be operational for 4 weeks during the 2010 Census. The Be Counted forms are to be available in English, Chinese, Korean, Russian, Spanish, and Vietnamese.

The Bureau developed the Service-Based Enumeration program (SBE) for the 2000 Census to provide the homeless and others without conventional housing an opportunity to be included in the census. The program involves visiting selected service locations such as shelters, soup kitchens and regularly scheduled mobile food vans that serve people without conventional housing. The Bureau reported that during the 2000 Census, the large percentages of historically undercounted populations were among the 171,000 people in emergency and transitional shelters enumerated through the program. For 2010, the Bureau plans to conduct address list updates of SBE locations by obtaining information about SBEs from the Internet and soliciting information from government agencies and advocacy organizations.

In-Language Questionnaires and Other Efforts

The Bureau intends to notify respondents through the Integrated Communications Campaign that if a questionnaire in one of the 5 languages other than English (Chinese, Korean, Russian, Spanish, or Vietnamese) is needed, the respondent should call the number provided on the questionnaire. The Bureau plans to provide language assistance guides for 59 languages, an increase from 49 languages in 2000. New in 2010, the Bureau plans to send bilingual questionnaires to approximately 13 million households that are likely to need Spanish assistance, as determined by analyzing recent data from the American Community Survey (a related Bureau survey program). Moreover, for 2010, the Bureau plans a multi- part approach for replacement mailings that includes a blanket mailing of approximately 25-30 million replacement questionnaires to census tracts with low response rates several weeks after the initial questionnaire mailing.

Challenges and Opportunities to Reduce Undercount

Although each of the operations I’ve described can position the Bureau to address the undercount, they also face challenges and uncertainties that, if not adequately resolved, could reduce the effectiveness of the Bureau’s efforts.

For example, with respect to address canvassing, the Bureau plans to provide listers with GPS-equipped handheld computers (HHC) to verify and correct addresses. Consequently, the performance of the HHCs is critical to the accurate, timely, and cost-effective completion of address canvassing. However, the Bureau’s ability to collect and transmit address and mapping data using the HHC is not known. For example, the 2008 Dress Rehearsal—which was an opportunity for the Bureau to conduct development and testing of systems and prepare for the 2010 Census— revealed a number of technical problems with the HHC that included freeze-ups and data transmission issues. The problems with the HHC prompted the Bureau to make major design changes, and a limited field test is scheduled for December 2008 (GAO is making plans to observe this test). However, if after this test the HHC is found to be unreliable, the Bureau will have little time to make any refinements.

Operations that were not tested during the Dress Rehearsal also introduce risks. These operations include the Be Counted program, Service-Based Enumeration, and Group Quarters Enumeration. Although the Bureau employed these operations during the 2000 Census, the Dress Rehearsal afforded the Bureau an opportunity to see how they might perform in concert with other activities planned for 2010, as well as identify improvements that could enhance their effectiveness.

The Integrated Communications Campaign faces its own set of challenges, chief among which is the long-standing issue of converting awareness of the census to an actual response. As a rough illustration of this challenge, various polls conducted for the 2000 Census suggested that the public’s awareness of the census was over 90 percent. Yet, as noted earlier, (1) the actual return rate was much lower—around 74 percent of the nation’s households, and (2) the Bureau’s evaluation of the 2000 Census Partnership and Marketing Program found that it only had mixed success in encouraging actual participation.

With respect to the partnership program, the Bureau plans to have 144 partnership staff, including specialists, on-board nationwide by the end of September 2008, and ramp up to 680 partnership staff by 2010. According to Bureau officials, although this level of staffing is about the same as for the 2000 Census, the Bureau believes it is sufficient, and plans to deploy the partnership specialists more strategically by allocating more partnership specialists to regions with large hard-to-count populations. For example, the Atlanta region, (which includes Florida, Alabama, and Georgia), had 50 partnership specialists in 2000, but is to receive more than 70 partnership specialists in 2010. Although the strategic deployment is a reasonable approach, the impact of the reallocation on those regions that will receive fewer partnership specialists is unclear.

Our evaluation of the 2000 Census Partnership Program found that there were mixed views regarding the adequacy of specialists staffing levels. Although partnership specialists we spoke to generally agreed that the Bureau hired enough specialists to carry out their activities, the managers of local census offices we interviewed noted that the partnership specialists' heavy workload may have limited the level of support they were able to provide. In 2010, to the extent that partnership specialists in regions with lower staffing levels wind up working with as many or more groups compared to 2000, or need to cover large geographic areas, they could find themselves thinly spread.

Our observations during the 2000 Census highlighted some best practices that appeared to be key to successful partnership engagements, and might help the Bureau refine its partnering efforts in 2010. For example, best practices for partners include (1) identifying ‘census champions’ (i.e., people who will actively support the census and encourage others to do so), (2) integrating census-related efforts into partners’ existing activities and events, and (3) leveraging resources by working with other partners and customizing census promotional materials to better resonate with local populations. For the Bureau, best practices include (1) providing adequate and timely information, guidance, and other resources to local partners on how they can support the census; (2) maintaining open communications with partners; and (3) encouraging the early involvement of partners in census activities.

Another challenge lies in staying on schedule. In order to meet legally mandated data reporting requirements, census activities need to take place at specific times and in the proper sequence. For example, the Group Quarters Validation operation needs to be completed after the Address Canvassing operation; the Questionnaire Assistance Centers need to be properly staffed, equipped, and opened by a particular date; advertising needs to be synchronized with various phases of the enumeration; and the questionnaires and replacement mailings all need to be carried out at the right time. Given the tight deadlines, small glitches could cascade into significant problems with downstream operations.

Another challenge will be to develop management information systems capable of tracking key operations to enable the Bureau to quickly address trouble spots. The Bureau did this successfully in 2000 with the system it used to track local census offices’ progress in meeting their recruiting goals. At those offices where recruiting was found to be lagging, the Bureau was able to quickly raise pay rates and take other actions that enabled the Bureau to meet its goal. Less successful was the management information system used to track the Bureau’s partnership efforts in 2000, which was found to be slow and not user-friendly, among other shortcomings, which limited its use as an effective management tool. For 2010, the Bureau intends to use a Web-based system that will enable it to manage the partnerships in real-time and determine, among other things, whether staff need to be redirected or reallocated.

Potential Impact of Undercounts on Federal Funding

Our past work indicates that the accuracy of state and local population estimates may have an effect, though modest, on the allocation of grant funds among the states. Many of the formulas used to allocate grant funds rely upon measures of population, often in combination with other factors. In our June 2006 report, we analyzed the sensitivity of Social Services Block Grants (SSBG) to alternative population estimates, such as those derived by statistical methods that incorporate the number of people that were overcounted and undercounted in the census, rather than the actual census.

To analyze the prospective impact of estimated population counts on the money allocated to the states through SSBG, we recalculated the state allocations using statistical estimates of the population that were developed for the 1990 and 2000 Censuses in lieu of the actual census numbers. We used the population estimates, which are based on the 2000 Census counts, and then adjusted these population estimates by the difference between the 2000 official population counts and the statistical estimates of the population.

We selected SSBG for our analysis because the formula for this block grant program, which was based solely on population, and the resulting funding allocations, were particularly sensitive to such alternative population estimates. In short, as shown in figure 6, in 2004, 27 states and the District of Columbia would have gained $4.2 million and 23 states would have lost $4.2 million of the $1.7 billion in SSBG funding. Based on our simulation of the funding formula for this block grant program, the largest percentage changes were for Washington, D.C., which would have gained 2.05 percent (or $67,000) in grant funding, and Minnesota, which would have lost 1.17 percent (or $344,000). While the shifting of these funding amounts may not seem significant in total, using an inaccurate count to allocate grant funds could adversely impact some states’ ability to provide services to their residents. Reducing the undercount will alleviate this potentially adverse impact to states.

This simulation was done for illustrative purposes only—to demonstrate the sensitivity of government programs to alternative population estimates that incorporate the number of people that were overcounted and undercounted in the census. Only the actual census numbers should be used for official purposes. This illustration further emphasizes the importance of an accurate decennial count.

Concluding Observations

The Bureau’s strategy for reducing the differential undercount appears to be comprehensive, integrated, and based on lessons learned from the 2000 Census. If each of the various components is implemented as planned, they will likely position the Bureau to address the differential undercount. Still, the various programs we examined are generally in the planning or early implementation stages, and a number of uncertainties and challenges lie ahead as the activities become operational. Indeed, past experience has shown how the decennial census is an enormous and complex endeavor with numerous moving parts, and any shortcomings or missteps can have significant consequences for the ultimate cost or accuracy of the enumeration.

With this in mind, the success of the Bureau’s efforts aimed at the hard-to- count will depend in large part on the extent to which they (1) start and finish on schedule, (2) are implemented in the proper sequence, (3) are adequately tested, and (4) receive appropriate staffing and funding. It will also be important for the Bureau to have a real-time monitoring capability to track the progress of the enumeration, target the Bureau’s resources to where they are most needed, and to quickly respond to various contingencies that could jeopardize the accuracy or cost of the count. In the months ahead, it will be important for Congress and the Bureau to continue to focus on these issues, as well as to be alert to newly emerging challenges.

Chairman Carper, Senator Coburn, and Members of the Subcommittee, this concludes my prepared statement. I would be happy to respond to any questions you may have.

If you have any questions on matters discussed in this testimony, please contact Robert Goldenkoff at (202) 512-2757 or by email at goldenkoffr@gao.gov. Other key contributors to this testimony include Ronald Fecso, Chief Statistician; Signora May, Assistant Director; Nicholas Alexander; Thomas Beall; Sarah Farkas; Richard Hung; Andrea Levine; Lisa Pearson; Sonya Phillips; Timothy Wexler; and Katherine Wulff.

Related GAO Products

2010 Census: Census Bureau’s Decision to Continue with Handheld Computers for Address Canvassing Makes Planning and Testing Critical. GAO-08-936. Washington, D.C.: July 31, 2008. 2010 Census: Plans for Decennial Census Operations and Technology Have Progressed, But Much Uncertainty Remains. GAO-08-886T. Washington, D.C.: June 11, 2008. 2010 Census: Bureau Needs to Specify How It Will Assess Coverage Follow-up Techniques and When It Will Produce Coverage Measurement Results. GAO-08-414. Washington, D.C.: April 15, 2008. 2010 Census: Population Measures Are Important for Federal Funding Allocations. GAO-08-230T. Washington, D.C.: October 29, 2007. 2010 Census: Diversity in Human Capital, Outreach Efforts Can Benefit the 2010 Census. GAO-07-1132T. Washington, D.C.: July 26, 2007. 2010 Census: Census Bureau Has Improved the Local Update of Census Addresses Program, but Challenges Remain. GAO-07-736. Washington, D.C.: June 14, 2007. 2010 Census: Redesigned Approach Holds Promise, but Census Bureau Needs to Annually Develop and Provide a Comprehensive Project Plan to Monitor Costs. GAO-06-1009T. Washington, D.C.: July 27, 2006.

Federal Assistance: Illustrative Simulations of Using Statistical Population Estimates for Reallocating Certain Federal Funding. GAO- 06-567. Washington, D.C.: June 22, 2006. 2010 Census: Planning and Testing Activities Are Making Progress. GAO-06-465T. Washington, D.C.: March 1, 2006. 2010 Census: Basic Design Has Potential, but Remaining Challenges Need Prompt Resolution. GAO-05-9. Washington, D.C.: January 12, 2005.

Decennial Census: Lessons Learned for Locating and Counting Migrant and Seasonal Farm Workers. GAO-03-605. Washington, D.C.: July 3, 2003.

Decennial Census: Methods for Collecting and Reporting Data on the Homeless and Others without Conventional Housing Need Refinement. GAO-03-227. Washington, D.C.: January 17, 2003. 2000 Census: Review of Partnership Program Highlights Best Practices for Future Operations. GAO-01-579. Washington, D.C.: August 20, 2001.

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