OMAHA, Neb. (AP) — The Omaha and Lincoln areas saw big population gains over the last decade while most rural areas continued to decline, a trend that will shift more political power to both cities, based on U.S. Census data released Thursday.

The report shows that Sarpy County grew at the fastest rate in the state, 20%, between 2010 and 2020. The county, encompassing Omaha’s suburbs, had a population of 190,604 as of last year.

Douglas County gained the most overall residents, however, with a net increase of 67,416. The 13% increase brings the county’s total population to 584,526. The Omaha metro area, which includes surrounding counties, is now on pace to hit 1 million people by 2024, said David Drozd, research coordinator for the University of Nebraska at Omaha’s Center for Public Affairs Research

Lancaster County also grew by 13%, from 285,407 in 2010 to 322,608 last year, according to the data.

Douglas, Lancaster and Sarpy counties now account for 56% of the state’s overall population, Drozd said. He said the gains will translate into an urban majority in the Nebraska Legislature, with big cities controlling an estimated 27 of the 49 seats.

Overall, 24 of Nebraska’s 93 counties gained at least some population. But the big three were the only ones that grew by more than 10%.

“That is quite a differential compared to all the other counties,” Drozd said.

Meanwhile, McPherson County in west-central Nebraska became the state’s least populated county, with 399 residents in 2020 after losing 140 people over the decade. Previously, the smallest county had been neighboring Arthur County, which has a new official population of 434.

Drozd said he was surprised more small counties didn’t post at least modest growth, as often happens every decade. He said underreporting may be a factor, because many of the smaller counties had a lower response rate.

Nebraska lawmakers will use the new data to redraw the state’s political boundaries, including legislative and congressional districts, in a special session scheduled for next month. On Thursday, several advocacy groups called on lawmakers to conduct the process in a transparent manner.

“When redistricting is fair, transparent and includes everyone, our maps are more likely to be representative and secure free, fair and responsive elections for the next decade,” said Gavin Geis, executive director of Common Cause Nebraska.

Danielle Conrad, a former state senator who served on the 2011 redistricting committee, said it’s critical that lawmakers approach the process with the goal of creating districts that give equal influence to residents throughout the state.

“The maps Nebraska’s state senators develop this fall will shape our lives and communities for the the next 10 years,” said Conrad, now the director of the American Civil Liberties Union of Nebraska.

Statewide, Nebraska’s population increased by 7.4%, to 1,961,504.

The state’s Hispanic or Latino population grew by 40.2%, from 9.2% of the population in 2010 to 12%. The Black population grew from 4.5% of the population to 4.9%.

The white population in Nebraska in 2020 was 78.4% of the population, down from 86.1% in 2010.

The release of the redistricting data culled from the 2020 census comes more than four months later than expected due to delays caused by the pandemic. The redistricting numbers states use for redrawing congressional and legislative districts show where white, Asian, Black and Hispanic communities grew over the past decade.

It also shows where populations have become older or younger, and the number of people living in dorms, prisons and nursing homes. The data covers geographies as small as neighborhoods and as large as states. Another set of data released in April provided state population counts and showed the U.S. had 331 million residents last year, a 7.4% increase from 2010.