The Affordable Care Act provides for premium tax credits that will assist millions of Americans in the purchase of health insurance on the newly-created Exchanges. 26 U.S.C. § 36B. The plaintiffs contend that the Act does not provide for tax credits for participants in federally-facilitated Exchanges. They are simply mistaken, however, in their reading of the Act. Congress made clear that an Exchange established by the federal government stands in the shoes of the Exchange that a state chooses not to establish. See 42 U.S.C. § 18041(c)(1). The Treasury Department, accordingly, reasonably interprets the Act to provide for eligibility for the tax credits for individuals in every state, regardless of which entity operates the Exchange.