Chicago City Wire

Cook County experienced a greater population loss than any other county in the United States between mid-2015 and mid-2016, according to statistics released by the U.S. Census Bureau, as more than 19,000 residents left the Chicago metro area in that time.

Meanwhile, sunnier climes like Arizona and Texas continue too see a boom in growth. Maricopa County, Arizona (Phoenix), and Harris County, Texas (Houston), were No. 1 and No. 2 , respectively, on the bureau’s list of counties experiencing the highest annual population growth. Maricopa grew by roughly 222 people every day.

Cook County and Chicago were at the forefront of a statewide trend that saw 93 of Illinois' 102 counties dealing with outmigration – people moving from one state to another. The nonprofit Illinois Policy Institute said a poll showed high taxes were the biggest reason given for leaving the state, but not the only one.

“Illinois’ dysfunctional government, weak job creation and ever-increasing tax burden help explain why,” it said.

As for the growing trend in the Southwest, the bureau said it was not -- perhaps surprisingly -- caused by international immigration, including from nearby Mexico.

"While net international migration has not reached prior levels, net domestic migration and natural increase have continued to rise, making Maricopa County this year's largest numeric gainer,” Peter Borsella, a bureau demographer, said.