The Census Bureau kicked off a shortened redistricting season Thursday with the release of detailed mapmaking data from last year’s count, as most states across the country scramble to finish their maps in time for next year’s midterm elections.

A handful of states, including Ohio and Colorado, face redistricting deadlines before the end of September. Others, like Texas, will have to draw their maps in a special legislative session.

Those mapmakers will be working with the most diverse data ever, as demographers redesigned questions to determine how Americans identify themselves. The Hispanic or Latino population grew to 18.7 percent, or 62.1 million, of the 331 million population, and the Black, Asian and mixed race population grew as well. The U.S. white-alone population fell below 60 percent for the first time in the nation’s history.

The population nationally grew by 7.4 percent, the smallest growth rate since the 1930s. People identifying as white alone declined nationally by 8.6 percent over the past decade, and Illinois, Michigan and West Virginia all lost population overall, along with Puerto Rico.

The data also shows an acceleration of population growth in the nation’s cities and suburbs. Population growth was “almost entirely in metro areas,” according to Marc J. Perry, a senior demographer in the agency’s population division.

The release comes after months of delay due to the coronavirus pandemic as well as decisions made by the Trump administration. The agency delayed the release to clean the data and implement new privacy protections.

“The data we are releasing today meet our high data quality standards,” Census Bureau acting Director Ron Jarmin told reporters Thursday.

Every state, except the six smallest, will have to redraw congressional district lines, and litigation has already started in several states over the new maps. Democratic-aligned groups in Pennsylvania, Minnesota and Louisiana have sued over the process. The parties have split control over state government in each of those states, making a deadlock over new maps likely.

While some national tables were released with news articles by the Census Bureau staff, detailed data with age, race and ethnicity down to the hyperlocal level that came out Thursday is in a “legacy” format that is more difficult to use. Next month, the agency plans to release user-friendly tools to look at the data. In the meantime, states and local governments will dive in to draw new maps.

The complications from the pandemic as well as decisions made by the bureau and the Trump administration have put the data released Thursday under a microscope. Experts will take the next several weeks — while states are drawing their new maps — to assess how accurate the count was.

The Census Bureau faced numerous problems during the count and afterward that many worry will skew the data. Last year, the agency had to scramble its plans amid the coronavirus pandemic and the Trump administration’s effort to rush the release of apportionment counts.

After Thursday’s release, the agency may still face another lawsuit. Alabama, along with members of the state’s Republican congressional delegation, sued earlier this year over the late release and the bureau’s new privacy protections.

Alabama argued the privacy protections would go too far, scrambling the data too much to be used for redistricting. That suit has been in a holding pattern after an appellate court ruled the state could not prove it had been harmed without the changed data — which the Census Bureau released Thursday.

Additionally, the American Statistical Association and the Committee on National Statistics plan on releasing reports about the accuracy of census results later this year.

The Census Bureau will next start releasing detailed data about housing and population, as well as a key post-census survey the agency uses to guess how many people it missed in the 2020 count itself. That effort after the 2010 census showed the agency overcounted hundreds of thousands of white people and homeowners while missing an almost equal number of minority communities and renters.