Full opinion text
POOLER, Circuit Judge: This case requires us to consider challenges to certain aspects of New York’s administration of its responsibilities under the federal Medicaid Act, 42 U.S.C. § 1396a et seq. (“Medicaid Act” or “Medicaid Statute”). Plaintiffs, certain health-service providers designated under federal law as Federally Qualified Health Centers and a trade association representing a number of FQHCs (together, “FQHCs” or “Health Centers”) assert various challenges to New York’s methods of reimbursing them for services they provide under Medicaid. They seek injunctive relief under 42 U.S.C. § 1983 to remedy these alleged shortcomings in New York’s method for providing Medicaid payments for the services the Health Centers provide. The Health Centers’ suit, at present, names M.D. Nirav Shah, Commissioner of the New York State Department of Health, (“Commissioner”) as defendant. On cross-motions for summary judgment, the United States District Court for the Southern District of New York (Andrew L. Carter, Jr., /.), for the most part upheld the Commissioner’s methods for reimbursing FQHCs for services they provide pursuant to Medicaid, but granted prospective relief to the Health Centers for reimbursement for certain services they provide to patients enrolled with Medicaid Managed Care Organizations (“MCOs”). Cmty. Healthcare Ass’n of New York v. New York State Dep’t of Health, 921 F.Supp.2d 130 (S.D.N.Y.2013). We agree with the district court that, as to the questions presented on appeal— with only one exception — there are no disputed issues of material fact, and that summary judgment was therefore appropriate. See Fed.R.Civ.P. 56(a). We further agree with the district court’s approach to, and analysis of, the majority of the issues before us. We thus affirm the grant of summary judgment to the Commissioner on most issues involving his methodologies for reimbursing FQHCs, and affirm the grant of summary judgment to the FQHCs on issues involving their reimbursement for services provided to MCO enrollees. However, we find that the district court erred in concluding that there were no disputed issues of material fact with respect to the Commissioner’s methodology for calculating its prospective obligation to make a wraparound payment to FQHCs that provide services pursuant to a contract with an MCO, see 42 U.S.C. § 1396a(bb)(5). We therefore vacate in limited part the district court’s grant of summary judgment to the Commissioner and remand for the district court, after resolution of these factual disputes, the compatibility of this methodology with 42 U.S.C. § 1396a(bb)(5). Affirmed in part, vacated and remanded in part. BACKGROUND We are concerned here with two competing objectives: “the mission of publicly-funded health clinics to provide a panoply of medical services to under-served communities, on the one hand,” Cal. Ass’n of Rural Health Clinics v. Douglas, 738 F.3d 1007,1009 (9th Cir.2013), and the necessity that- there be a “measure of discretion [states have] in choosing how to expend Medicaid funds,” Cmty. Health Ctr. v. Wilson-Coker, 311 F.3d 132,134 (2d Cir.2002), on the other. This measure of discretion, in turn, is premised on the recognition that states receiving Medicaid funds must be permitted to develop Medicaid programs that are responsive to the needs of their respective communities, so long as these programs are consistent with federal Medicaid requirements, a statutory arrangement that the Supreme Court has recognized as “designed to advance cooperative federalism.” Wis. Dep’t of Health and Family Svcs. v. Blumer, 534 U.S. 473, 497, 122 S.Ct. 962, 151 L.Ed.2d 935 (2002). This cooperative arrangement is of a piece with what has long been recognized as “one of the happy incidents of the federal system,” namely, “that a single courageous state may ... serve as a laboratory; and try novel social and economic experiments without risk to the rest of the country.” New State Ice Co. v. Liebmann, 285 U.S. 262, 311, 52 S.Ct. 371, 386-87, 76 L.Ed. 747 (1932) (Brandéis, J., dissenting). New York, as the administrator of the country’s largest and most expensive Medicaid program — with an annual budget exceeding $50 billion dollars — is currently engaged in such an experiment. In this pursuit, it has attempted to balance: the needs of low-income patients served by Medicaid and other federal programs; the missions, goals, and constituencies of health-care providers, in particular the community health centers who are plaintiffs in this case; and the possibility of achieving both cost-savings and better health outcomes that can result from contracting with MCOs to provide Medicaid services. With limited reservations, we conclude that federal law permits New York to pursue the path it has chosen. I. Federally Qualified Health Centers as Medicaid Service Providers The federal government established the Medicaid program via the passage, in 1965, of Title XIX of the Social Security Act, now codified at 42 U.S.C. § 1396 et seq. Medicaid is one of two programs, along with Medicare, through which the United States “subsidizes health care for persons” other than federal employees. Wilsonr-Coker, 311 F.3d at 133. Unlike Medicare, which primarily services the elderly and the disabled and depends on “intermediaries[ ] who must apply a uniform set of standards established by federal law ... Medicaid ... is designed to partially compensate States for the costs of providing health care to needy persons of modest income.” Id. at 134 (internal citations omitted). Thus, “States need not participate in the program, but if they choose to do so, they must implement and operate Medicaid programs that comply with detailed federally mandated standards.” Three Lower Cnties. Comm. Health Svcs., Inc. v. Maryland, 498 F.3d 294, 297 (4th Cir.2007) (internal quotation marks omitted). The Secretary of the Department of Health and Human Services (“HHS”) is responsible for overseeing state compliance with federal standards for implementing Medicaid programs. N.J. Primary Care Ass’n, Inc. v. N.J. Dep’t of Human Svcs., 722 F.3d 527, 529 (3rd Cir.2013). Within HHS, the Centers for Medicaid and Medicare Services (“CMS”) is responsible for exercising the “delegated authority” to oversee state compliance with federal Medicaid requirements. Sai Kwan Wong v. Doar, 571 F.3d 247, 250 (2d Cir.2009) (“Congress has entrusted the Secretary of HHS with administering Medicaid, and the Secretary, in turn, exercises that delegated authority through the CMS.”). To determine state eligibility for Medicaid funds,, the state “must submit a plan detailing how the State will expend its funds.” Wilson-Coker, 311 F.3d at 134. As relevant here, “[o]ne federal requirement is that a state Medicaid plan provide payment for services rendered by [FQHCs].” Three Lower Cnties., 498 F.3d at 297. The FQHC designation is also a creature of federal law. As Medicaid was designed to ensure medical services for “needy persons of modest income,” Wilsorir-Coker, 311 F.3d at 134, so also we have explained that FQHC grants -were similarly designed to ensure access to health services for “medically underserved communities.” Id. at 134 n. 2. The constituencies served by Medicaid and by FQHCs are not identical, however. “An FQHC is an entity receiving direct grants from the United States to provide primary and other health care services to [these underserved communities]. In addition to receiving direct grants, an FQHC can also bill for providing Medicare or Medicaid services. This dual funding mechanism allows the FQHC to allocate most of its direct grant dollars towards treating those who lack even Medicare or Medicaid coverage.” Id. (internal citations omitted); see also Three Lower Cwties., 498 F.3d at 297 (“[Plaintiff] is therefore not only a ‘health center’ receiving funds under the Public Health Service Act but also, by definition, an FQHC receiving funds under the federal Medicaid program.”). From the creation of dual funding sources for FQHCs, in the form of direct federal grants and indirect federal Medicaid dollars filtered through the states, FQHCs faced regulatory problems that, at least in part, compromised their mission to treat a constituency of “those who lack even ... Medicaid coverage.” WilsonCoker, 311 F.3d at 134 n. 2. The federal grant program for FQHCs was established in 1975, as Section 330 of the Public Health Services Act. See Special Health Revenue Sharing Act of 1975, Pub.L. 94-63, § 501, 89 Stat. 304, now codified at 42 U.S.C. § 254b. At the outset, the Ford Administration objected to the program as one which would provide services that duplicate those reimbursable under Medicare and Medicaid. S. Rep. 94-29, at 5-6, reprinted in 1975 U.S.C.C.A.N. 469, 472-73. Because of the overlapping mandate for Health Centers, and the various statutory gaps that allowed for states to avoid full payment to FQHCs for their service to Medicaid patients, the result for FQHCs by 1989, was that on average, Medicaid payment levels to [FQHCs] cover less than 70 percent of the costs incurred by the centers in serving Medicaid patients. The role of the programs funded under section[] ... 330 ... is to deliver comprehensive primary care services to underserved populations or areas without regard to ability to pay. To the extent that the Medicaid program is not covering the cost of treating its own beneficiaries, it is compromising the-ability of the centers to meet the primary care needs of those without any public or private coverage whatsoever. H.R.Rep. No. 101-247,392, reprinted in 1989 U.S.C.C.A.N.1906, 2118. Congress remedied this problem by legislating in 1989 that states receiving funds under Medicaid would be required “to reimburse FQHCs for ’100 percent ... of [each FQHC’s] costs which are „ reasonable.’ ” Three Lower Cnties., 498 F.3d at 297 (alterations and omission in original) (quoting 42 U.S.C. § 1396a(a)(13)(C) (repealed 2000)). “Congress’ purpose in passing this ... requirement was to ensure that health centers receiving funds under § 330 ... would not have to divert Public Health Services Act funds to cover the cost of serving Medicaid patients.” Id. The statutory scheme of reimbursement to FQHCs for services for which they were entitled to reimbursement under Medicaid was changed again in 2000. “To relieve health centers from having to supply new cost data every year, Congress amended the Medicaid Act in 2000 to implement a new prospective payment system based on historical costs plus a cost-of-living factor.” Id. at 298 (emphasis in original). This is the system at issue in this case. In pertinent part, the current statutory scheme requires that “the State plan shall provide for payment [to FQHCs] for such services in an amount (calculated on a per visit basis) that is equal to 100 percent of the average of the costs for the center or clinic of furnishing such services during fiscal years 1999 and 2000 which are reasonable and related to the costs of furnishing such services, or based on such other tests of reasonableness as the Secretary prescribes____” 42 U.S.C. § 1396a(bb)(2). “This rate-setting mechanism is known as the Prospective Payment System (“PPS”).” N.J. Primary Care Ass’n, Inc., 722 F.3d at 529. The rate for repayment is also indexed to keep pace with cost of living increases. 42 U.S.C. § 1396a(bb)(3); see also Three Lower Cnties., 498 F.3d at 298. “The system of states reimbursing FQHCs for their Medicaid costs is complicated considerably by the fact that many states ... use a managed care approach to running their Medicaid system.” Rio Grande Cmty. Health Ctr., Inc. v. Rullan, 397 F.3d 56, 62 (1st Cir.2005). The use of managed care, according to the Commissioner, “has become increasingly prominent in the Medicaid system nationwide.” The majority of Medicaid patients treated by FQHCs in New York are in fact enrolled by an MCO. Under this system generally, the state does not directly reimburse health service providers that serve Medicaid recipients. Rather, the state enters into a contract with an MCO. The state then pays the MCO for each Medicaid patient enrolled with it. The MCO, in turn, contracts with a health service provider, such as an FQHC, to provide medical services to its enrollees. See generally Rio Grande Cmty. Health Ctr., 397 F.3d at 62. The Commissioner submits that the benefits of such arrangements include “costs savings” that result “from an emphasis on preventive and primary care, as opposed to emergency care, historically a principal means by which underserved populations have accessed medical treatment.” The Health Centers, for their part, explain how federal law was designed to encourage MCOs to contract with FQHCs for provision of Medicaid services to MCO enrollees. Prior to the 1997 Balanced Budget Amendment (“BBA”), Pub.L. No. ■ 105-33, 111 Stat. 251, formerly codified at 42 U.S.C. § 1396a(13)(c)(1999), MCOS were required by the Medicaid Act to reimburse FQHCs “the full amount of the 100 percent reasonable cost” of providing services. See generally N.J. Primary Care Ass’n, Inc., 722 F.3d at 540-41. The current arrangement, however, adopted in 1997 and now codified, with little amendment, at Section 1396a(bb)(5)(A), places the obligation on states to reimburse FQHCs as follows: “In the case of services furnished by a[n] [FQHC] ... pursuant to a contract between the center ... and a[n] [MCO] ... the State plan shall provide for payment to the center or clinic by the State of a supplemental payment equal to the amount (if any) by which the [PPS] amount ... exceeds the amount of the payments provided under the contract.” In short, if an FQHC contracts with an MCO, and under this contractual arrangement an MCO pays the FQHC for services at a rate that is less than the PPS rate, the FQHC must still be made whole by the state. Furthermore, these “wraparound” payments are to be distributed to FQHCs “in no case less frequently than every 4 months.” Id. § 1396a(bb)(5)(B). The payment method for reimbursing FQHCs for services which they provide pursuant to Medicaid may also be established by an “alternative payment methodology.” Id. § 1396a(bb)(6). This methodology may be used only if it “is agreed to by the State and the [FQHC] and ... results in a payment to the [FQHC] which is at least equal to the amount otherwise required to be paid ... under this section.” Id. II. Methodologies for FQHC Reimbursement in New York The New York State Department of Health (“DOH”) is the New York entity responsible for administering New York’s Medicaid program. In addition to ensuring New York’s Medicaid compliance with state law, the DOH must also ensure New York’s compliance with federal laws and regulations. After the passage of 42 U.S.C. § 1396a(bb), New York passed corresponding state legislation to meet its obligations to pay FQHCs at a PPS rate. See N.Y. Pub. Health L. § 2807(8). Because the passage of Section 1396a(bb) also worked a substantive change in the administration of state Medicaid programs, the DOH was also responsible for submitting to CMS a State Plan Amendment (“SPA”) indicating how it would comply with the new method of prospectively reimbursing FQHCs for providing Medicaid services. See 42 C.F.R. § 430.12(c). Section 1396a(bb) was scheduled to be implemented for “services furnished on or after January 1, 2001,” 42 U.S.C. § 1396a(bb)(l). The DOH spent 2001 first reviewing various billing practices of FQHCs during 1999 and 2000, and then submitting various iterations of its SPA, SPA 01-03, proposing a PPS methodology to CMS, in an effort to acquire approval. SPA 01-03 was approved by CMS in April 2002. DOH also later submitted an additional proposed SPA, SPA 06-11, to CMS proposing changes as to how FQHCs would be reimbursed for providing certain offsite and group psychotherapy services, which was approved by CMS in 2006. Since the passage of Section 1396a(bb), New York has also made certain other changes or updates to the ways in which FQHCs are to be compensated for providing Medicaid services. In 2004, DOH issued guidance to FQHCs, among. other Medicaid service providers, in one of its periodic “Medicaid Updates” (“Medicaid Update”, or “2004 Update”) urging that non-emergency dentist visits should include both a cleaning and an exam as part of the same visit. The 2004 Update was issued because certain Medicaid service providers were performing cleanings and examinations on separate visits, increasing the number of visits for which it was possible to bill Medicaid. Finally, DOH has also implemented various policies to satisfy its obligation to pay FQHCs a statutorily guaranteed wraparound rate if the FQHC contracts with an MCO.42 U.S.C. § 1396a(bb)(5). Neither the dental billing update nor the calculation of New York’s prospective wraparound obligation was ever approved by CMS. These policies also have never been promulgated officially as New York regulations. A. CMS-Approved Methodologies Two of the payment methodologies challenged here, New York’s general PPS rate and its PPS rate for certain offsite services provided by FQHCs, have been specifically approved by CMS pursuant to its authority to review amendments to state plans. 42 C.F.R. § 430.12. 1. New York’s PPS Rate Both parties are in agreement on the content of New York’s PPS rate. As the district court explained: In New York, the PPS rate for reimbursement to FQHCs is the lower of allowable costs, as defined by state regulations, or the applicable peer group ceiling. [DOH] first considers each FQHCs patient care costs (“allowable costs”) from two base years. DOH then classifies allowable costs as either capital or operating costs and further classifies the operating costs into six categories [including administrative, patient transportation, medical, dental, and therapy, and ancillaries]. The six categories of operating costs are divided by the total number of patient visits to the FQHC, yielding the FQHC’s average per-visit costs. The average per-visit costs are compared to ceilings, based on the operating costs of other diagnostic and treatment centers, including non-FQHCs, located in the same region (upstate rural, upstate urban and downstate). The ceiling is 105% of the peer group’s average costs, by service category. Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 134. 2. New York’s Rate for Offsite and Group Psychotherapy Services CMS has also approved a specific New York PPS rate for certain services that FQHCs provide offsite. Again, the district court ably summarized the content of this rate in proceedings below, and the parties do not dispute it. CMS approved reimbursement of group therapy and offsite services performed by FQHCs at special rates, lower than the full PPS rates[ ] ... CMS permitted rates of payment for group psychotherapy and offsite services to be calculated using elements of the CMS-promulgated Resource Based Relative Value Scale. Furthermore, CMS required Medicaid reimbursement for offsite services only if provided to existing patients of the FQHC and where the offsite services were necessitated by health or medical reasons. Id. B. 2004 Medicaid Update Regarding Provision of Dental Services The DOH periodically issues “Medicaid Updates.” These updates “address, among other things, guidelines and policies for Medicaid billings and payments.” App’x at 460-61. In the 2004 Update the DOH advised clinics as follows. Non-emergency initial visits should include a cleaning, x-rays (if required), and a dental exam with a definitive treatment plan. Generally, this should be accomplished in one visit. However, in rare instances, a second visit may be needed for completion of these services. We would expect a notation in the record to indicate the reason for a second visit. App’x at 471 (emphasis in original). The concept of a “visit” is central to managing Medicaid costs. As the Commissioner explains, basing Medicaid reimbursement to centers on visits rather than discrete services “reflects a policy that the services provided in a visit to a clinic should be determined by the medical needs and circumstances of a patient, rath- . er than the clinic,’s desire to maximize reimbursement.” The parties here disagree as to whether DOH’s 2004 Update worked a change in billing practices by FQHCs with respect to reimbursement under Medicaid for the provision of dental services. Plaintiffs assert that “[w]hen PPS rates were calculated for plaintiff health centers, using the center’s 1999 and 2000 reasonable costs, the health centers were then providing dental examinations and cleanings during separate visits.” The result, according to the Health Centers, is that “the State’s consolidation requirement ... has an effeet that violates the federal law governing the manner in which an FQHC must be reimbursed by the Medicaid program (§ 1396a(bb)). That is, it changes what was in fact two visits (in the base years) to one visit without an adjustment to the affected FQHC’s per visit rate (to account for the resulting higher cost per visit).” The Commissioner disputes the evidentiary basis for the Health Centers’ claim that scheduling cleanings and examinations on separate visits was common practice in 1999 an'd 2000. Additionally, the Commissioner claims that “[t]he guidance did not represent any change in policy; it merely made clear that any FQHCs that were scheduling separate visits for ... the related services of dental cleanings and examinations [were doing so] contrary to longstanding DOH regulations.” C. New York’s Methodology for Determining the Wraparound Rate in the Case of FQHC and MCO Contracting 1. Prospective Calculation of the Wraparound Rate Section 1396a(bb)(5) also includes specific requirements for the states to provide supplementary, or “wraparound,” payments to FQHCs in the event that the FQHCs provide services pursuant to a-contract with an MCO. New York has never received specific approval from CMS for any iteration of its methodology, past or present, for calculating the wraparound payments that are owed to FQHCs. As the district court explained, the final SPA submitted to CMS included terminology with respect to the supplemental payment obligation “that ... largely mimics the text of 42 U.S.C. § 1396a(bb)(5).... CMS did not approve a special methodology for supplemental payments.” Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 141-42. The Commissioner does not argue on appeal that its current methodology for calculating the supplemental payment is entitled to the same deference due one approved by CMS. The current wraparound payment methodology employed by New York is prospective. As the district court explained, the methodology for calculating the Supplemental Payment is laid out in the “NYS Managed Care Supplemental Payment Program for FQHCs Policy Document” (“Supplemental Payment Program”). Id. at 134. This supplemental payment “is the average difference between what that FQHC is paid by contracted MCOs and its specific blended medicaid rate for each year.” App’x at 629-30. That rate “is a weighted average of the center’s PPS rate, offsite service rate, and group counseling rate.” Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 135. The Health Centers object to the use of this rate on two grounds. The first objection is that, because Section 1396a(bb)(5) requires that the wraparound payment be “equal to” the difference between the amount paid, for each visit, to the FQHC by the MCO and the amount owed the FQHC under the PPS rate, New York cannot merely estimate its prospective wraparound payment using the previous years’ MCO visits and payments. Such estimates, the plaintiffs contend, cannot satisfy the statutory meaning of “equal to” as it is used in Section 1396a(bb)(5). The second objection is to how New York collects the information it uses to calculate the wraparound rate. The FQHCs submit to DOH a Managed Care Visit and Revenue Report (“MCVR Report”), which documents the previous year’s MCO visits and repayments. The FQHCs allege that the MCVR Report does not allow the FQHC to report a visit during which the FQHC provided services for which the MCO did not reimburse the FQHC. Thus, there is no provision for an FQHC to report certain visits to the DOH such that they might be included in the calculation of the prospective year’s .wraparound rate. The Health Centers allege that this reporting gap results in systematic underpayment to the FQHCs. The Commissioner, for his part, submits that FQHCs can put in a claim for a supplemental payment even if the MCO has not reimbursed the FQHC at the time the supplemental payment request is made. 2. MCO Non-Payment and Administrative Challenges The inability of FQHCs to report to DOH on visits which did not result in MCO payment for the purposes of New York’s wraparound rate calculus is also related to two independent challenges by the Health Centers with respect to New York’s obligations under Section 1396a(bb)(5). The Health Centers argue that New York fails to provide any avenues by which the Health Centers can challenge an MCO for non-payment for services. The result is that not only is New York’s prospective calculation of the supplemental payment short, but also that the service provided by the FQHC will not qualify as a service provided “pursuant to a contract” with an MCO, and thus not qualify for a supplemental payment under Section 1396a(bb)(5). The FQHCs argue they are left footing the entirety of the bill for services which they provided. The Health Centers bring a final challenge under Section 1396a(bb). They argue that there is no provision for payment to FQHCs in the event that the Centers provide services to an MCO enrollee that is outside of the network of the MCOs. The Commissioner argues that New York’s contracts with MCOs place this payment burden on MCOs, and thus MCOs are obligated to pay for these services. The Commissioner argues that Congress has made this option available to it under 42 U.S.C. § 1396b(m), which provides in relevant part that, in the case of medically necessary services which were provided (I) to an individual enrolled with the entity under the contract and entitled to benefits with respect to such services under the State’s plan and (II) other than through the organization because the services were immediately required due to an unforeseen illness, injury, or condition, either the entity or the State provides for reimbursement with respect to those services. 42 U.S.C. § 1396b(m)(2)(A)(vii). The Commissioner-argues that this provision of the Medicaid Act governing state-MCO contracting trumps the provisions of the Medicaid Act requiring full reimbursement to FQHCs for the services they provide, as mandated by Section 1396a(bb). III. Proceedings Below A. Summary Judgment After discovery, both parties cross-moved for summary judgment. The district court, in a thorough and cogent opinion, granted partial summary judgment and denied partial summary judgment to both parties. In addressing the FQHCs’ challenge to New York’s PPS methodology, the district court determined that “[s]ince the statute is ambiguous, the starting place is ... whether the federal agency has approved a permissible construction of the Medicaid Act.” Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 139. With respect to the Health Centers’ challenge to New York’s use of peer group ceilings, the district court noted that CMS had specifically asked the Commissioner to justify such an approach, and that the Commissioner had “responded that CMS had previously approved the use of peer group ceilings.” Id. It noted that “CMS addressed all of the concerns that Plaintiffs now try to argue merit dismissal of the peer group ceilings ... and still approved the SPA.” Id. Thus, the district court concluded that “the interpretation of the statute to allow peer group ceilings ... is, at the very least, a plausible one.” Id. It granted summary judgment to the Commissioner on this issue. With respect to the Health Centers’ challenge to the reimbursement for offsite and group therapy services, the district court again noted that “Congress’s intent about how offsite services and group therapy should be reimbursed is not explicitly set forth in the Medicaid statute,” and thus reasoned that it would “grant deference to CMS’s approval of” SPA 06-11 “setting reimbursement rates for these services.” Id. at 140. It concluded that “the prior .approval of CMS yielded a permissible construction that offsite services and group therapy services could be reimbursed at special rates that this court should not disrupt.” Id. It granted summary judgment to the Commissioner on this issue as well. With respect to the challenge to 2004 Update setting forth guidance on billing practices for dental services, the district court reasoned that “this statement in no way represents a new policy ... but rather the optimal standard of care.” Id. at 147. Noting that FQHCs are entitled only to “costs that are reasonable,” id. at 147 (citing 42 U.S.C. § 1396a(bb)), the district court granted summary judgment to the Commissioner on this issue. The district court next considered the challenges raised to New York’s supplemental payment methodology. It first concluded that CMS had not considered the methodology being challenged, and that it would thus review New York’s development of this methodology de novo. Id. at 142. With respect to the substantive validity of the Supplemental Payment Program,, the district court rejected the Health Centers’ argument that “there is a simple mathematical equation for determining supplemental payments.” Id. at 143. Noting the “multiple possibilities for calculating the PPS rate for any FQHC,” the district court concluded that the “range of options does suggest that States might retain some flexibility in how to adopt their own approaches in rate setting.” Id. at 143-44. Having rejected the Health Centers’ objection to a prospective approach to supplemental payment obligations as such, the district court noted that specific challenges based on the PPS rate and the rate of payment for offsite services had federal approval, and thus the supplemental payment methodology was not invalid on those grounds either. Id. at 144. It thus granted summary judgment to the Commissioner. Next, the district court considered New York’s policies with respect to non-payment to FQHCs by MCOs. The district court determined that “the fact that there is no mechanism by which FQHCs are reimbursed for services actually furnished under MCO contract and not paid by the MCO is troublesome and in clear contravention of the plain language of 1396a(bb)(5).” Id. at 145. It continued as follows: [T]he FQHC is the clear beneficiary of the statute and the State has a clear responsibility to make a supplemental payment “in the case of services furnished by a FQHC.” This supplemental payment must be equal to the amount by which the PPS rate exceeds the payments provided under the contract. Notably, the phrase “payments provided under the contract” permits deduction only of amounts actually paid by the MCO to the FQHC. Whether or not the MCO makes a payment, the State is responsible for the supplemental payment (which may in fact be the entire PPS rate, if the MCO fails to make a payment). There is rio basis for the State’s conclusion that the FQHC must accept the loss because the MCO denied payment for an otherwise legitimate visit. Determining the amount the MCO will pay is certainly necessary for the calculation of supplemental payments, but the MCO’s determination of validity cannot be the end of the inquiry. There are many reasons why a MCO might not pay an otherwise valid claim. To prevent fraudulent claims as the State certainly has an interest in doing, these payments might properly be reserved for a more robust audit or administrative process. The current audit process by DOH’s Bureau of Managed Care Certification and Surveillance is only available “on the grounds that the health care service' is not medically necessary or is experimental or investigational.” N.Y. Comp.Codes R. & Regs, tit. 10, § 98-2.1 (2013). Id. (some internal citations omitted). The district court granted summary judgment to the Health Centers on this issue and enjoined the Commissioner’s policy “until modified in the manner set forth in this Opinion.” Id. Turning to the issue of out-of-network reimbursement, the district court similarly concluded that “in the absence of a contract with an MCO, the State instead is wholly responsible for the reasonable costs of the FQHC at the prevailing PPS rate.” Id. However, given that Section 1396b(m)(2)(A)(vii) allows the state to contractually allocate to the MCO the obligation to pay for services provided by out-of-network FQHCs, the district court reasoned that “[tjhere is a conflict (or at least a substantial loophole) in the understanding of the Medicaid framework and the State-MCO contract.” Id. at 146. This is because under Section 1396a(bb)(5), the state is responsible for a gap between MCO and FQHC payment (in the form of the supplemental payment) but, in the case of out-of-network services, the state delegated FQHC payment to an MCO. Id. The district court reasoned that “the burden of this loophole should never fall on FQHCs, which are covered by the federal statute for their services.” Id. The district court thus enjoined “[t]he State’s failure to pay for out-of-network services not paid by the MCO.” id. at 147. Finally, the district court found that the balance of equities favored injunctive relief, id. at 148, and this determination is not challenged by the Commissioner on appeal. B. Injunctions Following its decision on summary judgment, the district court ordered the Commissioner to submit a “plan of action ... that, in the event of non-payment by the MCO, provides for (1) full reimbursement to FQHCs for services provided, subject to verification by the Commissioner; and (2) full reimbursement to FQHCs who provide Medically Necessary Services.” Special App’x at 31. The district court approved New York’s proposed plan on July 26, 2013. Special App’x at 34. There is no appeal from this order, and its scope and particulars are not before us. The Health Centers now appeal the various grants of summary judgment to the Commissioner, and the Commissioner cross-appeals the grants of summary judgment to the Health Centers. STANDARD OF REVIEW We review the grant of summary judgment de novo. Westport Bank & Trust Co. v. Geraghty, 90 F.3d 661, 668 (2d Cir.1996). Summary judgment is appropriate where “there is no genuine dispute as to any material fact and the movant is entitled to judgment as a matter of law.” Fed.R.Civ.P. 56(a). As in such a motion before the district court, on appeal “[t]he evidence of the non-movant is to be believed, and all justifiable inferences are to. be drawn in his favor.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 255, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986). DISCUSSION I. New York’s CMS-Approved Methodologies for PPS Payments are Entitled to Deference The Health Centers are challenging two methods for Medicaid reimbursement — the general PPS reimbursement rate developed by the DOH, and the special PPS rate for certain other services— which CMS specifically approved as amendments to the state plan. As eventually codified in New York, the general reimbursement rate was established by “grouping facilities to establish cost center ceilings” on a geographic basis. 10 N.Y.C.R.R. § 86-4.14(d). The cost center ceilings are “computed at 105 percent of the adjusted weighted average base year costs of the facilities in the cost center group.” 10 N.Y.C.R.R. 86-4.14(c). Of course, if an FQHC was operating at less than the peer group ceiling at the time that DOH was implementing its PPS methodolgy, then its per-visit rate for services reflects “that center’s actual operating costs per visit.” App’x at 485. The entirety of this methodology, and more, was proposed by New York, and reviewed by CMS, in a series of eight letters exchanged between March 29, 2001, and April 12, 2002. DOH first submitted SPA 01-03, proposing the general PPS methodology implementing the prospective change for FQHC reimbursements to CMS on March 29, 2001. CMS asked specifically what “the State’s proposed methodology ... [PPS], or an alternative methodology? If New York chooses the PPS methodology, it should explain- its derivation.... If the State chooses to implement an alternative methodology, the methodology must be agreed to by the State and each center/clinie.” App’x at 308. After a series of letters between DOH and CMS, which further clarified CMS’s concerns and required DOH to make certain adjustments to its proposed amendment, on February 5, 2002, CMS explicitly requested information regarding the use of both peer-group ceilings, and an explanation of the reasons for reimbursing FQHCs at a rate that was “the lower of’ the 105 percent reimbursement and a given center’s average costs. App’x at 330. On March 18, DOH responded, “Peer groups are established by grouping facilities offering similar types of services and having similar regional economic factors.” App’x at 335. Explaining the 105 percent cost ceiling, DOH explained that it “allows for variability of costs within the peer group.” Id. In its next letter, CMS approved SPA 01-03 on April 12, 2002. DOH submitted SPA 06-11, for CMS approval on February 27, 2006. Now codified at 10 N.Y.C.R.R. 86-4.9(h)-(i), this amendment proposed to make FQHCs eligible for receiving reimbursement for providing group psychotherapy and offsite services. Both of these services are reimbursed at a rate which DOH calculates “using elements of the [Resource] Based Relative Value System (RBRVS) promulgated by [CMS].” App’x at 379. CMS asked for further guidance regarding the exact methodology that DOH would apply to calculate the value of these services, and the DOH responded by laying out for CMS the precise formula it would apply in order to derive the payment rate for group psychotherapy and offsite services. On October 30, 2006, CMS approved SPA 06-11. We have not yet spoken on the proper level of deference that we are to afford to CMS in a case such as this, namely, where CMS has specifically approved, after consultation with a state agency, the state’s adoption of an SPA. The closest that we have come to the issue is Wilson-Coker, where we were called to determine the deference owed to a state plan that incorporated a CMS-developed, though not officially-promulgated, “productivity screen.” Wilson-Coker, 311 F.3d at 134-35. A “productivity screen” is “[a] productivity standard [that] imposes a minimum visit requirement on affected providers, [such that] if a health care provider does not meet or exceed the minimum number of patient visits per year, its reimbursement is reduced in proportion to the amount by which the provider feel short of the minimum.” Id. at 134-35. Connecticut passed legislation to implement this screen, but state regulations to reflect these changes were not implemented until 2001, at which point CMS approved the use of screens. Plaintiff, an FQHC, challenged the use of screens during 1999 and 2000, which was relevant because those were the two baseline years for implementing a PPS methodology under Section 1396a(bb)(2), and as a result “shortfalls in that period will result in a reduction in the amount of money [an FQHC] receives in the future for each visit.” Id. at 136. We considered what would constitute a “reasonable cost” under Section 1396a(bb)(2), and specifically, whether a limitation based on a “productivity screen” could constitute such a cost. We noted that the phrase “reasonable costs” was ambiguous, id. at 137, and that “[i]n resolving this ambiguity, we owe some significant measure of deference to CMS’s interpretation of the statute, although we need not decide the exact molecular weight of the deference we accord to CMS’s position,” id. at 137-38. We then reversed the decision of the district court on the ground that its interpretation of reasonable and related costs was inconsistent with CMS’s position. Id. at 139. The general lesson of Wilson-Coker, then, is that CMS’s interpretation is probative of the meaning of the repayment provisions to FQHCs laid out in Section 1396a(bb). Other circuits to consider this issue have been unanimous in holding that a CMS decision approving an SPA is entitled to deference under Chevron, U.S.A., Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 104 S.Ct. 2778, 81 L.Ed.2d 694 (1984). See Managed Pharmacy Care v. Sebelius, 716 F.3d 1235,1240 (9th Cir. 2013) (“[T]he Secretary’s approval of California’s requested reimbursement rates ... is entitled to deference under Chevron.”); Christ the King Manor, Inc. v. Sec’y of U.S. Dep’t of Health and Human Sens., 730 F.3d 291, 307 (3rd Cir.2013) (“SPA approvals are ... the type of agency action that warrants Chevron deference .... ”); Harris v. Olszewski, 442 F.3d 456, 467 (6th Cir.2006) (“[T]he agency’s approval of the state plan amendment is entitled to Chevron deference.”); Pharm. Research and Mfrs. of America v. Thompson, 362 F.3d 817, 822 (D.C.Cir.2004) (holding the “Secretary’s interpretations of the Medicaid Act are ... entitled to Chevron deference”). “[Administrative implementation of a particular statutory provision qualifies for Chevron deference when it appears that Congress delegated authority to the agency generally to make rules carrying the force of law, and that the agency interpretation claiming deference was promulgated in the exercise of that authority.” United States v. Mead Corp., 533 U.S. 218 226-27, 121 S.Ct. 2164, 150 L.Ed.2d 292 (2001); see also Christ the King Manor, Inc., 730 F.3d at 306. And, while the Supreme Court has not spoken directly on the issue, in Douglas v. Independent Living Center of Southern Calif, “the Supreme Court said that ‘[t]he Medicaid Act commits to the federal agency the power to administer a federal program,’ and that, in approving a[n] SPA ‘the agency has acted under [that] grant of authority.’ ” Christ the King Manor, Inc., 730 F.3d at 306 (alterations in original) (quoting —• U.S. -, 132 S.Ct. 1204,1210, 182 L.Ed.2d 101 (2012)); see also Managed Pharmacy Care, 716 F.3d at 1246. Thus, agency approval “ ‘carries weight,’ especially when ‘the language of the particular provision at issue ... is broad and general.’ ” Christ the King Manor, Inc., 730 F.3d at 306 (omission in original) (quoting Douglas, 132 S.Ct. at 1210). We find the reasoning of our sister circuits on this issue persuasive. And this reasoning compels the conclusion that New York’s CMS-approved PPS methodologies are permissible under Section 1396a(bb). Under the familiar two-part Chevron analysis, we are “require[d] to abide by an agency’s interpretation or implementation of a statute it administers if Congress has not directly spoken ‘to the precise question at issue’ and if the agency’s answer is ‘permissible’ under the statute.” Managed Pharmacy Care, 716 F.3d at 1246 (quoting Chevron, 467 U.S. at 842-43, 104 S.Ct. 2778); see also Sash v. Zenk, 428 F.3d 132, 136-38 (2d Cir.2005) (applying two-step Chevron framework to ambiguous statute governing good behavior credits for federal prisoners). It is beyond debate that Congress did not speak precisely as to the methodology for calculating the PPS rate in Section 1396a(bb)(2). We have already held as much with respect to Section 1396a(bb)(l), which requires that “the State plan shall provide for payment for services” furnished by FQHCs, but does not specify a particular payment' method for states to use. Wilsortr-Coker, 311 F.3d at 139. Section 1396a(bb)(2), as well, includes the same language regarding the state’s obligation to provide^ for payment, but specifies that this payment must be “equal to 100 percent of the average of the costs of the center or clinic ... during fiscal years 1999 and 2000 which are reasonable and related to the costs of furnishing such services, or based on such other tests of reasonableness as the Secretary prescribes in regulations.” The Secretary has not provided such tests of reasonableness. Wilson-Coker, 311 F.3d at 137, leaving us with the alternative provision of Section 1396a(bb)(2). Congress did not prescribe any single method as the only way in which states would be permitted to calculate average reasonable and related costs. In Section 1396a(bb)(2), Congress has left this to the states and CMS to develop, in trusting the partnership and spirit of “cooperative federalism” that Medicaid envisions, Wis. Dep’t of Health and Family Svcs., 534 U.S. at 496, 122 S.Ct. 962, to result in a methodology which will give meaningful and appropriate content to the term. It remains for us to determine, then, whether CMS, in approving an SPA that made arrangements for calculating average costs based on a methodology that imposed cost-ceilings based on regional groupings was approving a PPS. methodology that was “permissible” within the meaning of Section 1396a(bb). Chevron, 467 U.S. at 842-43, 104 S.Ct. 2778. We have no problem concluding, as the district court did, that such an approach is well within the range of permissible readings of the statute. Nothing in the statutory FQHC-reimbursement provisions forbids states from grouping similar FQHC providers in its initial analysis of services provided during 1999 and 2000. The mere fact that the FQHCs believe these groupings to be arbitrary does not establish that they are impermissible under Section 1396a(bb)(2); this is especially true given that the FQHCs have produced no evidence at summary judgment that such groupings actually result in FQHCs being reimbursed at a rate less than that required to cover their costs of providing services. Indeed, even if they did, an individual FQHC could still appeal for an adjustment to this reimbursement if the services it provides are “unique within [its] peer group.” App’x at 211. We affirm the district court’s judgment with respect to SPA 06-11, also approved by CMS, for substantially similar reasons. It is clear that the Medicaid Act does not speak directly to the question of how to reimburse FQHCs for the offsite and group psychotherapy services covered in SPA 06-11, and in light of the Commissioner’s submission that such services ought to be reimbursed at a lower rate because they “do not present the same costs for an FQHC that a standard individual clinic does,” an assertion that goes unchallenged by the Health Centers, we think such a policy entirely permissible under the statute, Chevron, 467 U.S. at 842-43,104 S.Ct. 2778. The Health Centers mount an additional collateral attack on CMS’s approval of this special rate for offsite and group therapy services. They assert that this special PPS rate must be analyzed under Section 1396a(bb)(6) rather than Section 1396a(bb)(2). Section 1396a(bb)(6) allows for a state to make reimbursement to FQHCs for services “under an alternative payment methodology that — (A) is agreed to by the State and the center ...; and (B) results in a payment to the center ... of an amount which is at least equal to the amount otherwise required to be paid to the center ... under this section.” The Health Centers assert, that the special PPS rate is an alternative payment methodology and that, because they have not agreed to it, it is invalid under this provision. The Health Centers’ reading of the statute is simply untenable. The statute contemplates three methods for FQHC reimbursement: first, through the general PPS rate set by states with CMS approval, 42 U.S.C. § 1396a(bb)(2); second, through reimbursements that are “based in such other tests of reasonableness as the Secretary prescribes,” id.; and third, through a general “alternative payment methodology” whose availability is codified at Section 1396a(bb)(6). Thus Section 1396a(bb)(6) cannot be read to modify the provisions of a general PPS rate under Section 1396a(bb)(2). Rather, “alternative” means what it says, namely, that Section 1396a(bb)(6) allows states and FQHCs, if in agreement with one another, to eschew the PPS methodology of Section 1396a(bb)(2) altogether. See Pee Dee Health Care, P.A. v. Sanford, 509 F.3d 204, 207 (4th Cir.2007) (“The Medicaid Act ... allows for two methods of reimbursement. The first method is a ‘prospective payment system’ based on historical-average costs plus a cost-of-living factor. 42 U.S.C. § 1396a(bb)(2). The second method, set forth in § 1396a(bb)(6), authorizes an ‘alternative payment methodology’ that can take a number of forms.” (footnote omitted)); Rio Grande Cmty. Health Ctr., Inc., 397 F.3d at 62 (describing requirements of Sections 1396a(bb)(2)-(3) and noting that “[a] state may only deviate from the very specific payment methodology of the PPS if the FQHC involved gives its consent and there is no reduction in the total payments made as compared to the PPS method”). The Health Centers’ contrived reading of Section 1396a(bb)(6) would make every deviation in payment for provision of separate services an “alternative payment methodology.” We reject such a reading. ‘We take care not lightly to disrupt the informed judgments of those who must labor daily in the minefield of often arcane policy, especially given the substantive complexities of the Medicaid statute.” Wilson-Cok&r, 311 F.3d at 138. The Health Centers fail to explain why we ought to abandon this principle here. Despite every opportunity to produce evidence that the decisions at issue impacted their bottom line, they are left at this point only with the bald assertion that New York’s methodology in aggregate costs them millions of dollars. But this assertion is not tethered to any evidence in the record, but only to DOH documents calculating each Center’s original PPS rate. This evidence does not create a genuine dispute of material fact as to whether the FQHCs actually have been shortchanged under the PPS system. It certainly does not provide us with justification to upset the considered determination of DOH and CMS. II. The State’s 2004 Guidance Letter Regarding Payment for Dental Services Did Not Work an Unreasonable Change on the Baseline Calculation for Payment for Services During the 1999 and 2000 Fiscal Years The Health Centers next argue that the 2004 Medical Update, which encouraged all Medicaid service providers (not just FQHCs) to provide dental cleaning and examination services during the same visit is unlawful. FQHCs may still be reimbursed for cleaning and examination services provided on separate visits. However, the billing statement must include a notation that explains why services were offered on separate visits. The Health Centers argue that this change works an effect on the rates set, because “it changes what was in fact two visits (in the base years [1999 and 2000]) to one visit without an adjustment to the affected FQHC’s per visit rate (to account for the resulting higher cost per visit).” We disagree with the Health Centers that the change worked by New York’s 2004 Medicaid’ Update results in an impermissible state policy under Section 1396a(bb)(2). The Health Centers direct us to absolutely no language in the statute, nor to a principle of interpretation, that would help us to recognize their contention regarding New York’s dental billing practices guidance as a legal argument, rather than a mere observation. The Health Centers argue that they may succeed in challenging New York’s dental billing practices “even if the State’s consolidation requirement reflects the proper standard of care.” This argument verges on the self-refuting. Section 1396a(bb)(2) contemplates only reimbursement for the “reasonable and related costs” of providing services to FQHC patients.' We may grant the Health Centers’ argument that their “literal heap of evidence” established that it was the practice of Health Centers with dental clinics to bill for separate visits for dental examinations and teeth cleanings (a proposition on which we remain agnostic). However, there is no evidence in the record that such a practice conformed with the proper standard of care. And the Commissioner has submitted evidence that there are at least two justifications for requiring these services to be provided in a single visit. First, it decreases the transportation costs of each visit, which Medicaid is required to reimburse. Second, the Commissioner argues that a multi-visit policy results in inconvenience to patients, who are forced to make multiple trips when one would suffice. Even construing this evidence in the light most favorable to FQHCs on this point, as we must, we have no difficulty concluding that requiring FQHCs to provide two dental services in a single visit, or explain why it did not do so, is an eminently “reasonable” requirement under Section 1396a(bb)(2). As such, even if the FQHCs were providing these services in two visits during 1999 and 2000, New York cannot be required to make an adjustment to a Health Center’s PPS rate based on this set of circumstances. The mere fact that FQHCs were engaging in practices that led DOH, perhaps mistakenly, to credit them for costs not reasonably related to the provision of services during the time that the DOH was calculating PPS rates for FQHCs does not mean that FQHCs were entitled to rely on that unreasonable practice in perpetuity. So long as the current rate, and application of New York billing practices, reflects only “reasonable” costs, it is in compliance with Section 1396a(bb)(2). To be fair to the FQHCs, we note that there might well be important justifications for an FQHC to provide dental examinations and dental cleanings on separate visits. We can imagine, for example, that because FQHCs are often remotely located it might be impossible to staff an FQHC for both services on the same day, or that an FQHC may only wish to provide one or the other of the services based on community needs, and so forth. The Medicaid Update provides what we consider to be a costless solution to this .conundrum, by allowing FQHCs to annotate the justification for billing unbundled dental services. The FQHCs provide no explanation as to why this is not a reasonable solution. III. New York’s Methodology with Respect to Making Supplemental Payments to FQHCs Does Not Fully Satisfy the Requirements of Section 1396a(bb)(5) In addition to challenges to the PPS method for establishing each Health Center’s reimbursement rate pursuant to the general requirements of Section 1396a(bb)(l)-(2), the Health Centers also challenge New York’s methodology for making reimbursement payments to Health Centers that provide services pursuant to a contract with an MCO. Section 1396a(bb)(5) contemplates such an arrangement, requiring that in such a situation, “[i]n the case of services furnished by a[n] [FQHC] ... pursuant to a contract between the center ... and a managed care entity ... the State plan shall provide for payment to the center or clinic by the State of a supplemental payment equal to the amount (if any) by which the amount determined under paragraph (2) [and] (3) ... of this subsection exceeds the amount of payments provided under the contract.” Paragraphs (2) and (3), as already described, first lay out the state’s general PPS methodology for per-visit payments, and also set out the rate by which these payments increase going forward, to keep pace with inflation. 42 U.S.C. § 1396a(bb)(2)-(3). The statute thus contemplates that there will be a difference in the amount that the MCO contracts to pay the FQHC. In keeping with the general goal of Congress to ensure that FQHC grants do not subsidize Medicaid generally, Congress has provided that the FQHC grants should also not subsidize Medicaid managed care. And it is also in keeping with the Congressional goal that FQHCs should provide Medicaid services to MCO enrollees: prior to this statute, the requirement was that MCOs would have to contract with FQHCs to pay the full rate for services themselves. See generally N.J. Primary Care Ass’n, Inc., 722 F.3d at 540-41. The deletion of this provision allows MCOs to negotiate their own rate for FQHC care of MCO enrollees, incentivizing MCOs to contract with FQHCs. The state’s responsibility remains to avoid allowing Section 330 Medicare grants to cross-subsidize Medicaid programs. See Three Lower Cnties., 498 F.3d at-297. CMS has never approved New York’s methodology for providing payment of the difference between an FQHC’s PPS rate and the amount provided for under the contract between the MCO and the FQHC. SPA 01-03 “at least mentioned the supplemental payment methodology.” Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 141. However, New York’s methodology for calculating this payment, as laid out in SPA 01-03, closely tracks the language of 42 U.S.C. § 1396a(bb)(5). “Any supplemental payment methodology was not based on the agency’s expertise or consideration of the State’s interpretation of the supplemental payment methodology as consistent with the Medicaid requirements.” Id. at 141-42. As this presents a question of law, our review of New York’s methodology for calculating this supplemental payment to FQHCs is de novo. See Turner v. Perales, 869 F.2d 140, 141 (2d Cir.1989) (“[T]he question is whether the state law and implementing regulations are consistent with federal law. This is an issue of law, subject to de novo review in federal court... .”)■. The current supplemental payment “is the average difference between what [the] FQHC is paid by contracted MCOs and its specific blended Medicaid rate for each year. The blended Medicaid rate is a weighted average of the center’s PPS rate, offsite service rate, and group counseling rate.” Cmty. Healthcare Ass’n of New York, 921 F.Supp.2d at 135 (internal quotation marks omitted). The Health Centers raise a number of objections to this policy. We may dismiss one immediately. Having resolved the Health Centers’ challenge to the use of a special rate for offsite and group services above, we And nothing objectionable in their inclusion in New York’s wraparound methodology. Next, the Health Centers challenge New York’s general policy of employing a' prospective methodology to establish an FQHC’s wraparound rate. The Health Centers contend that such a method conflicts with the substantive provisions of Section 1396a(bb)(5), in particular its requirement that states reimburse FQHCs in amounts that are “equal to” the difference between the Center’s PPS rate and the amount paid by the MCO. The district court rejected this challenge, as do we. A. Section 1396a(bb)(5) Permits a Prospective Methodology for Calculating Wraparound Rates The Health Centers challenge, as a general matter, New York’s decision to employ a prospective method for calculating a given Health Center’s wraparound rate using data from the previous year’s Medicaid eligible encounters. Importantly, they do not challenge the use of any of the specific inputs in this calculation, such as the Medicaid blended rate, outside of the challenges to the PPS and other inputs in this calculation which we have already found, above, to be compliant with the requirements of Section 1396a(bb). The crux of the Health Centers’ argument is that Section 1396a(bb)(5) requires that the wraparound payment be “equal to” the difference between the rate paid to the Centers as a result of the PPS rate, and the amount paid to the Centers by the MCOs. Thus, the Health Centers conclude that Section 1396a(bb)(5) sets up a “ ‘simple equation’ that results in a precise number.” We cannot endorse the Health Centers’ unnecessarily restrictive reading of Section 1396a(bb)(5). It is true that “[w]hen the statutory language is plain, the sole function of the courts ... is to enforce it according to its terms.” Arlington Cent. Sch.