Why millennials are fleeing Mississippi — and flocking in droves to these US states

New data on interstate millennial migration is raising eyebrows and concerns for some state leaders while elevating hopes for others.

The U.S. Census Bureau on June 22 released its latest research on the nation's aging population, which included details on generational demographics and geographic population shifts.

The research shows the Millennial population, people born between 1981 and 2000, is growing in most states and has increased by 2.6 million nationwide since 2010, according to Governing.

In 2015, millennials surpassed Baby Boomers as the nation's largest age demographic group, but their numbers aren't increasing in every U.S. state.

Millennials are fleeing Mississippi.

Mississippi led the nation in millennial population decline between 2010 and 2016, when 3.9% of millennials left the state, according to the Sun Herald.

Less than 802,000 millennials currently reside in Mississippi.

Other southern states, including Alabama and Arkansas, also saw millennial declines, but Mississippi's more than doubles Alabama's 1.8% decrease, making it the state with the most millennial flight.

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State Rep. Noah Sanford, 27, told Mic that Mississippi's rural landscape makes it less popular among young adults.

Jackson, Mississippi, the state capital, is the only city in the state with more than 100,000 people, according to the Advocate. Gulfport, Mississippi, is the only other city in the state with more than 50,000 residents.

"We have the third highest percentage of our population that live in rural areas," Sanford said Wednesday. "Young people by in large don't return to their small towns in rural areas. They go to urban centers and suburbs."

That explanation somewhat conflicts with the two states attracting the most millennials these days.

Utah and Alaska are seeing an influx of millennials.

While Washington, D.C., has the highest percentage of millennials per capita, according to Governing, Utah and Alaska rank first and second respectively among states for net positive millennial migration.

The reasons appear to be economic.

Utah's capital, Salt Lake City, was recently named the No. 1 place for older millennials to live, according to the website Realtor.

Older millennials, ages 25 to 34, currently make up the largest group of homebuyers in Salt Lake City, according to Realtor economic research analyst Sabrina Speianu.

"[Salt Lake City] already has a higher than normal share of 25-to-34-year-olds in its population," Speianu wrote in a March press release. "It is also one of the fastest growing metros in terms of population and jobs, and has the lowest unemployment rate of the top markets."

In Alaska, people in their 20s currently make up 15% of the state population and 27% of people moving there, according to the state Department of Labor.

"We have an age profile that shows generally this has been the case for a while," state demographer Eric Sandberg said Wednesday. "Kids leave here at ages 18 to 19 for college, giving us a net migration loss. At about age 21 to 22, we start getting large immigration to Alaska. That immigration remains positive through the rest of their 20s."

The state has nine military bases, including Elmendorf-Richardson, near Anchorage, which Sandberg said brings in a major influx of young adult soldiers every year.

But it's Alaska's job market that sets it apart from most states.

"People come looking for jobs," Sandberg added. "For people without a college education, there's a fair amount of good jobs up here in the fishing industry, mining and the oil industry."

Alaska's outdoor recreational environment also attracts lots of new residents every year, according to Sandberg.

Legalizing recreational marijuana in 2015 was popular among millennials as well.

"Typically it's either jobs or lifestyle," Sandberg said. "It's maybe something people try for a while. When they get a little older, they leave the state."