While almost half of the 3,142 counties in the country decreased in population from 2010-18, Tarrant County saw a 15.15% increase—a jump from 1,810,655 residents to 2,084,931—in those eight years, making it one of the top 10 counties in the country in population growth, according to U.S. Census Bureau estimates released in April.

In 2018, there were 274,276 more residents in Tarrant County than in 2010, and most of that growth was due to domestic migration, which accounts for 84,464 people, Census data shows.

Tarrant County’s population growth of 27,463 in the last year was fueled by 12,618 residents moving into the area––of which 8,312 came from outside the U.S. and 4,306 relocated domestically, according to the statistics.

Out of 3,142 counties, 1,640 counties, or 52.2%, showed positive total net migration in 2018, meaning more people moved into the county than moved out, according to a Census press release.

“One interesting trend we are seeing this year is that metro areas not among the most populous ... are ranked in the top 10 for population growth,” said Sandra Johnson, a demographer in the Census Bureau’s Population Division, in the press release.

Some of Tarrant County's growth was due to new residents in cities such as Keller, Roanoke and Fort Worth. The city of Keller added 7,723 residents between 2010 and 2018, bringing its population estimate to 47,350 residents, according to Census data released May 23.

Roanoke, which is divided between Denton and Tarrant counties, added 3,123 residents during the eight-year time frame. Its estimated population in 2018 was 9,085 residents.

Fort Worth, which touches Tarrant, Denton, Wise and Park counties, saw the largest population increase between 2010 and 2018. The city tacked on 153,802 new residents, bringing its 2018 population to 895,008.

The Dallas-Fort Worth-Arlington and Houston-The Woodlands-Sugar Land metro areas each gained over 1 million people since 2010, according to 2018 population estimates.

With populations of 7,539,711 and 6,997,384, respectively, the Dallas-Fort Worth-Arlington and Houston-The Woodlands-Sugar Land metro areas are ranked the fourth and fifth most-populous metros behind New York, Los Angeles and Chicago.

The state’s overall population grew by over 3.5 million residents from mid-2010 to July 2018 for a total of 28.7 million residents, according to the Census.