A federal appellate court ruling threatens to raise the price of health insurance for millions of Americans who bought through HealthCare.gov. (Theresa Poulson/The Washington Post)

Jason Millman reports that the D.C. federal appellate court just ruled that the federal government isn't authorized to administer insurance subsidies in the 36 states that refused to set up their own health insurance exchanges. If those subsidies are ultimately banned -- which is uncertain, considering the 4th Circuit Court of Appeals released a conflicting ruling today upholding the subsidies -- millions of enrollees could see their premiums rise by as much as 76 percent. In total 4.7 million people - 58 percent of all Obamacare enrollees - could be affected.



And as a reminder, here are the 36 states that refused to set up their own exchanges:


For a more detailed breakdown of the size and prevalence of Federal exchanges, see the interactive map below.