Nearly a third of the nation’s counties look likely to have just a single insurer offering health plans on the Affordable Care Act’s exchanges next year, according to a new analysis, an industry pullback that adds to the challenges facing the law.

The new study, by the nonpartisan Kaiser Family Foundation, suggests there could be just one option for coverage in 31% of counties in 2017, and there might be only two in another 31%. That would give exchange customers in large swaths of the U.S. far less choice than they had this year, when 7% of counties had one insurer and 29% had two.

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