The results of the once-per-decade census form the basis for the number of House members and Electoral College votes per state, the redistricting of state legislative maps, and how much federal funding gets allocated for schools, hospitals, and public works, as well as for programs like Medicaid and grants for community mental-health services.
According to the report, the states with the most significant undercount rates were Arkansas (5.04 percent), Florida (3.48 percent), Illinois (1.97 percent), Mississippi (4.11 percent), Tennessee (4.78 percent), and Texas (1.92 percent).
States whose populations were overcounted were Hawaii, which had the highest rate with 6.79 percent, followed in order by Delaware, Rhode Island, Minnesota, New York, Utah, Massachusetts, and Ohio.
The 2010 census, by contrast, did not have any statistically significant over- or undercount rates, as noted by NPR.
Canvassing for the 2020 census was marred in part by the Covid-19 pandemic, as in-person interactions between strangers were widely discouraged. But also a factor was the “unprecedented” interference by the Trump administration, as one civil servant described it in a September 2020 memo. That memo detailed meddling in issues like the privacy of census respondents and pressure to quickly wrap up the counting of populations. In addition, the Trump administration sought (unsuccessfully) to count unauthorized immigrants separately from the population, and it attempted to add a citizenship question to the census until a federal judge blocked it.
The Trump administration put a stop to the census early, partly so that if Trump lost, he could reapportion the House before his term expired, The New York Times reported. Former Census Bureau directors testified before Congress that wrapping up the count early could mean that the administration essentially ignored as many as 6.5 million people — mostly from “Hispanic, immigrant, and foreign-born populations.” This March, unsurprisingly, the Census Bureau released a report indicating that Black people, Latinos, and Native Americans were undercounted, while white and non-Hispanic people were overcounted.
Officials from the bureau said at a press briefing Wednesday, according to NPR, that its overcount and undercount findings will not change the allocation of U.S. House seats or Electoral College votes for the next 10 years.