"[If] the federal government did not reimburse insurers for CSRs, insurers would increase plan premiums to cover these costs. As a result of the ACA's structure, these higher premiums would translate into higher federal costs for Premium Tax Credits (PTCs).... [T]he result would be a substantial increase in total federal costs ... In effect, the federal government would pay CSRs indirectly, through increased PTCs, at much greater total expense. This analysis focuses on the long-term consequences of not reimbursing insurers for CSRs."