The census was intended to be a snapshot of the country's population as of Census Day (April 1, 2020), so it was not supposed to count U.S. residents who died before that date, according to the bureau's residence criteria. People who died on or after April 1 last year should have been counted.

Is there information about race, ethnicity, age and sex, as well as population numbers for counties, cities, towns and other smaller areas, in these census results?

No, this information will be released with the second set of 2020 census results. This more detailed demographic information is needed for the redrawing of voting districts. It's also used to guide the distribution of an estimated $1.5 trillion a year in federal money for Medicare, Medicaid, education and other public services for local communities.

When will that demographic data be released?

The bureau plans to start releasing this information by Aug. 16. New redistricting data was due to the states by the end of March. But the bureau said it is behind schedule on running quality checks after the Trump administration pressured it to prioritize the new state numbers that former President Donald Trump wanted to alter before leaving office.

The timing may change, however, depending on how two lawsuits turn out. Alabama and Ohio are asking the federal courts to force the bureau to put out this data by the end of July so they can meet their state redistricting deadlines. Alabama's lawsuit is also trying to stop the bureau from adopting a new technique, known as differential privacy, for keeping personal information in anonymized census data confidential. If Alabama wins, the data's release would be delayed by "multiple months" past August, the agency's chief scientist said in a recent court filing.

How accurate are these census numbers?

It will be difficult to say for certain immediately. The bureau's career officials have said the agency has not found anything in the data suggesting the census is not "fit for its constitutional and statutory purposes."

But no U.S. census has been perfect. The pandemic and Trump officials' last-minute changes to the schedule have heightened concerns about how well certain groups were counted, especially historically undercounted groups who are less likely to participate in the census unless they receive in-person visits from door knockers. The Trump administration's failed push for a citizenship question may also have further discouraged households with immigrants and people of color from getting counted.

For the first time, the bureau is releasing quality metrics at the national and state levels on the same day it puts out the first numbers. But census experts say metrics at a more detailed level are needed because the quality of the count can vary greatly from neighborhood to neighborhood.

Researchers with the American Statistical Association are conducting an independent audit of the count's quality, and they are set to release their first report in June. The Census Bureau is conducting its Post-Enumeration Survey to estimate how many people may have been missed as well as rates of overcounting and undercounting among racial and ethnic groups. Those results are not expected to start rolling out until December.

Can we redo the census?

It's not clear if state population numbers from a do-over can be used to redistribute seats in the House of Representatives — the count's main purpose as outlined by the Constitution. Federal law does allow for a "mid-decade census" in 2025, but the results can't be used for reapportioning the House. There's also a question about money: Would Congress be willing to fund another head count shortly after what's estimated to be the most costly census in U.S. history at $15.6 billion?

What happens next to the first census results?

These state population counts and the new assignment of House seats are part of a handoff process involving the commerce secretary overseeing the bureau, the president and Congress. Ultimately, the numbers are certified by the clerk of the House, who is then charged with officially reporting them to the states.

Some states that have lost seats may sue the Biden administration to challenge how the House was reapportioned, and that may change some states' new number of congressional districts before next year's midterm elections. The new Electoral College map, with votes based on each state's latest share of seats in Congress, goes into effect beginning with the 2024 presidential race.

Correction: April 26, 2021 12:00 am — An earlier web and radio version of this story misattributed a quote from Kristin Koslap, senior technical expert on 2020 census congressional apportionment in the Census Bureau's Population Division, to Karen Battle, chief of the bureau's Population Division.

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