[pcwalton]

The very next two sentences: "The observed premium increase reflects unsubsidized premiums. Insurers receive the full premiums each month, regardless of whether they are paid by the individual or the federal government (IRS 2014). Thus, although the data reflect premiums received by insurers, individuals likely faced smaller changes in premiums after taking the subsidy into account."

It's remarkable that premiums didn't rise more under the ACA, despite how many new previously-uninsurable people were covered.