What did Henry Aaron mean? (A bleg)

In a NEJM paper this week , Henry Aaron wrote,

The ACA’s subsidies fully protect people receiving them through 2017 against growth of health insurance costs beyond specified fractions of income; thereafter, they provide partial protection against premium growth.

I either didn’t know this or forgot it. But now I can’t seem to find in the law or anywhere what, exactly, happens to subsidies after 2017. I thought they were tied to the cost of the second lease expensive “silver” rated plan. But then what? Anybody know and have a reference?


Hidden information below


Email Address*