by Patrick Appel

Nobody knows for certain:

In a new study, Chuck Blahous, who is a public trustee for Medicare and Social Security, concludes that the 2010 health law will add at least $340 billion to the federal deficit from 2012-2021. This is contrary to the official estimates by the Congressional Budget Office, which initially figured the Affordable Care Act would reduce the deficit by about $132 billion from 2012-2019. Who’s right? Who knows? In truth, unknowable and unpredictable changes in overall health costs will dwarf the variation between Chuck’s estimate and CBOs.

Ezra Klein takes Blahous's estimate much less seriously.