Census Analysis Finds Undercount But Not as Bad as Predicted

The 2020 census missed an estimated 1.6 million people, but given the hurdles posed by the pandemic and natural disasters, the undercount was smaller than expected, according to an analysis by a think tank that did computer simulations of the nation’s headcount.

The analysis, done by the Urban Institute and released Tuesday, found that people of color, renters, non-citizens, children and people living in Texas — the state that saw the nation’s largest growth — were most likely to be missed, though by smaller margins than some had projected for a count conducted in the midst of a global pandemic. Still, those shortfalls could affect the drawing of political districts and distribution of federal spending.

The analysis estimates there was a 0.5% undercount of the nation’s population during the 2020 census. If that modeled estimate holds true, it would be greater than the 0.01% undercount in the 2010 census but in the same range as the 0.49% undercount in the 2000 census.

“The fact that the undercount wasn’t larger is surprising and certainly a good news story,” said Diana Elliott, principal research associate at the Urban Institute. “This undercount suggests the 2020 census may not be as close in accuracy as 2010, but it may not be as dire as some had feared.”

The official undercount or overcount of the census won’t be known until next year when the Census Bureau releases a report card on its accuracy. The bureau’s post-enumeration survey measures the accuracy of the census by independently surveying a sample of the population and estimating how many people and housing units were missed or counted erroneously

About a fifth of the U.S. residents not counted in the Urban Institute’s simulations, or more than 377,000 people, lived in Texas, and that could have real-life consequences. According to the Urban Institute analysis, Texas stands to miss out on $247 million in 2021 federal Medicaid reimbursements for being undercounted.

President Joe Biden’s choice to head the Census Bureau, Robert Santos, was chief methodologist at the Urban Institute before his nomination last spring. He played an advisory role on the project, Elliott said.