A quarter of America's most rural counties have witnessed a jump in severely cost-burdened households.

Rural counties with spikes in such households range from Maine to Oregon.

Incomes in many rural areas are stagnating or even declining.

Housing has been famously unaffordable in expensive cities such as San Francisco for a while. But now in tiny towns and counties across the country, an increasing share of rural residents are struggling to pay their rents and mortgages.

The housing affordability crisis is spreading to rural communities such as Aroostook County, Maine, and Malheur County, Oregon, where the share of residents who are severely burdened by housing costs has surged since the housing crash of 2006 to 2010, according to the County Health Rankings. Other researchers are also calling attention to the issue, with Pew's Stateline finding that one of four of the country's most rural counties have seen a rise in severely cost-burdened households -- those that spend more than half their income on housing.

Fifty years ago, the most urgent issue for rural communities was substandard housing, such as whether residents relied on outhouses rather than indoor plumbing, noted Lance George, director of research and information at the Housing Assistance Council, a nonprofit focusing on rural housing. But affordability now ranks as the top housing concern among rural residents, he said.

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"You think it's often just with big cities," he said. "Housing costs are lower in rural areas, but incomes are pretty low too." Housing affordability is a "simple equation," George added. "It's incomes related to housing costs, and incomes in the lower quintile have not increased at all, and maybe even declined."

In other words, the affordability crisis in rural America is almost the inverse of the dynamics of cities such as New York, where rapidly rising incomes and a population surge are driving housing prices upward. In rural towns and counties, flat incomes for poor and moderate-income workers are partially to blame for the housing affordability crisis.

Older and poorer

Since 2009, rural America has fallen behind compared with the country's major metropolitan areas. Rural areas have lost residents during this time, while the country's biggest cities have swelled their populations by 8 percent, according to a December Goldman Sachs report. With younger residents leaving rural areas for jobs in cities, the median age of rural Americans is now 43, or six years older than the median age of city residents.

And when it comes to jobs -- an indicator of a local economy's vibrancy -- rural America is also stumbling. Job growth in top cities has climbed almost 14 percent, compared with less than 3 percent in rural America.

Poverty is also higher in rural regions, with 23 percent of households living on annual incomes below $21,000, or the 2018 federal poverty guideline. In large metropolitan areas, the share stands at about 17 percent.

"With lower median incomes and higher poverty rates than homeowners, many renters are simply unable to find decent housing that is also affordable," noted Tanya Eastwood, the chairman of the Council for Affordable and Rural Housing, in testimony for a Congressional hearing earlier this month on rural housing affordability.

Looming cuts?

The crisis may only worsen, said Housing Assistance Council's George. That's because of government programs that are ending or struggling to keep up with market changes, such as the U.S. Department of Agriculture's program to offer mortgages for affordable rental properties in rural areas. But funding for that program, called Section 515, has fallen off, with no direct financing since 2011, the HAC said.

On top of that, mortgages on properties that were financed with the USDA loans are maturing, which means the owners won't be obligated to rent at affordable prices, George said. Almost 1,800 affordable rental units will leave the program each year through 2027, the HAC forecasts.

The Trump administration's proposed 2020 budget also contains cuts for rural housing programs, Stan Keasling, president of National Rural Housing Coalition, said in testimony at the Congressional hearing earlier this month. The cuts target "a laundry list" of programs, including direct homeownership, home-repair loans, and loans and grants for rural rental housing.

"I worry this issue could get much greater if you don't see an increase in income" in rural regions, HAC's George said. "There's no doubt that affordability is the largest and most pressing housing challenge in rural communities."