The U.S. Census Bureau released a report today on population changes between July 1, 2015 and July 1, 2016. The U.S. Census Bureau released a report today on population changes between July 1, 2015 and July 1, 2016.[/caption]

Harris County’s eight-year run as the nation’s fastest-growing county has ended, according to estimates released by the U.S. Census Bureau today. Maricopa County in Arizona, home to Phoenix, has taken its place on the list as the county with the highest annual population growth after growing at a rate of nearly 2 percent.

Between July 1, 2015 and July 1, 2016, Maricopa gained 81,360 people—about 222 people daily. Harris County, now the second fastest-growing county, gained 56,587 people in that time—an average of 155 people daily.

Nearly 28,000 residents migrated to Harris County from other countries this year. The county's natural increase—total births minus total deaths—accounted for more than 46,000.

"In the early 2000s, Maricopa County was in the top one or two counties by numeric growth,” said Peter Borsella, a demographer in the Census Bureau’s population division. “From 2009-11, Maricopa County saw much lower net migration than in the years before or after, which caused the county to drop out of the top population-gaining counties. While net international migration has not reached prior levels, net domestic migration and natural increase have continued to rise.”

Harris County remains the nation’s third-largest county with 4.6 million people, closely followed by Maricopa County in fourth place with 4.2 million people. Los Angeles County still sits in the No. 1 spot, and Cook County in Illinois is second.

Other highlights from the report include:



  • Eight of the 10 counties with the most natural decrease were in Florida.

  • Three of the top 10 counties with the most natural increase were in Texas.

  • Four of the top 10 counties with the largest population gains were in Texas: Harris, Tarrant, Dallas and Bexar counties.

  • The nation’s 382 metropolitan areas contained more than 277 million people last year, or roughly 86 percent of the total U.S. population.

  • The Dallas-Fort Worth-Arlington and Houston-The Woodlands-Sugar Land areas were the two largest numeric-gaining metropolitan areas between 2015 and 2016, each increasing by more than 100,000 residents.

  • The Austin-Round Rock metropolitan area was one of four to be on both the 25 fastest growing and the 25 largest numeric gain lists. Net domestic migration was a primary contributing factor.


In the coming months, the Census Bureau will release 2016 population estimates for cities and towns, as well as national, state and county population estimates by age, sex, race and Hispanic origin. Find more highlights from this year's release below and local-level statistics on www.census.gov.