Census 2010 in US was "Outstanding" According to the Census

The US House of Representatives recently voted to drastically cut the Census Bureau's budget (although that is still waiting to be debated in the Senate), so this was a good time for the Bureau to announce the findings from its post-enumeration of the 2010 Census. A random sample of households are selected in this survey and the results are then compared with the census data. Dr. Robert Groves, Director of the Census Bureau, called the census "outstanding" based on the post enumeration survey results:

The results found that the 2010 Census had a net overcount of 0.01 percent, meaning about 36,000 people were overcounted in the census. This sample-based result, however, was not statistically different from zeroThe 2000 Census had an estimated net overcount of 0.49 percent and the 1990 Census had a net undercount of 1.61 percent.
As with prior censuses, coverage varied by race and Hispanic origin. The 2010 Census overcounted the non-Hispanic white alone population by 0.8 percent, not statistically different from an overcount of 1.1 percent in 2000.

The Census Bureau attributed the overcount largely to people who own multiple homes, since the census is based initially on household addresses

The 2010 Census undercounted 2.1 percent of the black population, which was not statistically different from a 1.8 percent undercount in 2000. In 2010, 1.5 percent of the Hispanic population was undercounted. In 2000, the estimated undercount of 0.7 percent was not statistically different from zero. The difference between the two censuses was also not statistically significant.

The Census Bureau attributed these undercounts largely to the fact that higher proportions of these race/ethnic groups are renters, and renters are traditionally harder to count than home owners.