2010 Census: Census Bureau Should Take Action to Improve the Credibility and Accuracy of Its Cost Estimate for the Decennial Census

In 2008, to improve the Bureau's life cycle cost estimates for the decennial census and to help establish a sound basis for the 2020 Census cost estimate we recommended the Census Bureau to thoroughly document the 2010 Census life cycle cost estimate. In February 2015, Bureau officials confirmed that the 2010 data is accessible and is informing the planning of the 2020 Census. In addition, a Bureau official explained that in moving forward, the Bureau will have all the 2020 documentation, including assumptions, sources of the data and method of calculation contained in a central standard format. Further, all of the 2020 Census data will be located in the Decennial Budget Integration Tool (DBiT), and the Bureau will use the GAO's Cost Assessment Guide in their estimation exercises.

Best practices for an accurate cost estimate require that assumptions be updated when costs change as new information becomes available. In our June 2008 report on the Census Bureau's 2010 Census life cycle cost estimate, we found that estimated costs had been understated for the address canvassing operation. Subsequently, in October 2009 we testified that address canvassing in 2009 ran 25 percent or $88 million over its initial budget of $356 million. Given the Bureau's past difficulties with accurate cost estimates, we were concerned about the reliability of the $2.7 billion cost estimate for non-response follow-up, the Bureau's largest field operation, when census workers go door to door in an effort to collect data from households that did not return their census form. Following our October 2009 testimony the Bureau took action and re-examined assumptions and other data used to support the cost estimate for nonresponse follow-up. For example, the Bureau reviewed field work assumptions (such as miles driven per case, pay rates, hours worked per week, and attrition) which the Bureau updated based on actual Census 2000 data, national and field tests, and address canvassing results. In February 2010, the Bureau re-estimated that it would cost approximately $2.3 billion to conduct nonresponse follow-up.

In 2008, we reported that the 2010 Census life cycle estimate was not current because it did not reflect actual costs. For the 2020 Census the Bureau has taken action to ensure the estimate is current. For example, for 2020 the Bureau intends to follow best practices, and will continually mature Census 2020 cost estimation methods in terms of detail and reliability throughout the decade based on the results of 2020 research, and as the scope and requirements for the 2020 Census unfold. As a first step, the Bureau produced a baseline 2020 rough order of magnitude cost estimate that in part was based on 2010 cost data. In addition, the new decennial budget integration tool has functionality that will also allow the Bureau to report cost variances and determine the factors that led to those differences.

Non-response follow-up is the largest and most costly field operation. In December 2009 the Bureau wanted to determine whether the current budget of $2.74 billion was sufficient to carryout the operation. The Bureau implemented our recommendation when it performed workload and productivity sensitivity analysis and determined that $2.33 billion was a reasonable amount for NRFU, a reduction of almost $400 million. In addition, for the 2020 Census the Bureau told us it planned to purchase commercial software that will perform sensitivity and uncertainty analyses using data from the Decennial Budget Integration Tool (DBIT) system.

In 2008 we recommended that the U.S. Census Bureau (Bureau) ensure it have staff resources qualified in cost estimation and that it establish policies, procedures, and guidance for cost estimation. The Bureau agreed and completed a skill gap analysis using GAO's Cost Estimation Guide in January 2009, that was followed by the development of a comprehensive training plan in April 2009. Further the Bureau plans to establish internal guidance for cost estimating.