More than half of the country's 498rating regions had only one or two insurers participating in theACA marketplace. Those regions are disproportionately in sparselypopulated areas. (Photo: Shutterstock)

The Affordable Care Act marketplace is struggling to deliver affordable premiums torural areas, largely due to a lack of insurance competition.

A new analysis by the Urban Institute, aliberal-leaning think tank, finds that more than half (271) of thecountry's 498 rating regions had only one or two insurersparticipating in the ACA marketplace. Those regions aredisproportionately in sparsely populated areas.

Meanwhile, the 69 regions that had five or more insurers werelargely in densely populated urban areas.

Related: What factors drove Obamacare signups in2018?

The Northeast was home to many of the regions with the mostrobust competition. Forty percent of the population in theNortheast lives in a region with five or more ACA health plans.

The opposite is true in the South, where only 4 percent of thepopulation lives in a region with five or more health plans.Fifty-two percent of people live in a region with one or twoplans.

In both the West and Midwest, roughly a quarter of thepopulation lives in a region with at least five ACA plans. However,a far greater proportion of the population in the Midwest islocated in areas with only one or two plans (40 percent vs. 19percent).

Regions with little competition tend to have much higherpremiums. In a region with only one insurer, the median benchmarkplan for a 40-year-old nonsmoker is $592 a month. That compares to$376 for the same consumer in a region with at least fiveplans.

Granted, the premiums do not reflect what the majority of ACAcustomers are paying, since the majority of them are eligible forpremium tax credits that significantly lower what they owe.

“It's encouraging to see signs of stabilization in theindividual market,” said Anne F. Weiss, managing director at theRobert Wood Johnson Foundation, which commissioned the analysis.“However, geographic location still plays too great a role inconsumers' coverage options and how much they cost. Everyone shouldhave affordable health insurance options, regardless of where theylive, given the impact of coverage on health.”

Read more: 

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• Number of marketplace competitors matters less thantype
• BCBS offers suggestions for shoring up theACA