Opinion by Judge PAEZ; Dissent by Judge ALARCÓN.
OPINION
PAEZ, Circuit Judge:In this opinion, we consider whether a settlement agreement between the Bonneville Power Administration (“BPA”) and a large number of its customers is lawful. We invalidated a previous settlement between BPA and a class of customers because it did not comply with the Pacific Northwest Electric Power Planning and Conservation Act (“NWPA”). See Portland Gen. Elec. Co. v. BPA, 501 F.3d 1009, 1036-37 (9th Cir.2007) (“PGE”); Golden Nw. Aluminum, Inc. v. BPA, 501 F.3d 1037, 1048 (9th Cir.2007) (“Golden Nw.”). On remand, BPA initiated a complex rate-making process, under which it calculated both (1) overcharges resulting from the. unlawful settlement, and (2) new rates, intended to comply with PGE and Golden Northwest. Its customers, in turn, filed numerous petitions for review in this court, challenging various aspects of BPA’s rate-making.1
In the face of potentially unending litigation, BPA and a large number of its customers entered into the Residential Exchange Program Settlement Agreement (“REP-12 Settlement Agreement” or “Settlement”). Record of Decision (“ROD”) 14.2 The Settlement sets terms for refunding customers who were previously over-charged, as well as setting terms— including a new rate-making methodology — for the next seventeen years. After a thorough evaluation, the BPA Administrator issued the REP12 Record of Decision, a final agency action, in which he adopted the Settlement and committed BPA to abide by its terms.
In its petition for review, the Association of Public Agency Customers (“APAC”) challenges the Settlement, alleging that it violates several provisions of the NWPA, 16 U.S.C. §§ 839c(c), 839e(b), the Bonneville Project Act, 16 U.S.C. § 832d(a), regulations of the Federal Energy Regulatory Commission, 18 C.F.R. §§ 300.1(b)(6), 300.21(e)(1), and this court’s decisions in PGE and Golden Northwest.3 In re*944sponse, BPA and the intervening parties argue, in part, that APAC’s members lack standing to bring this challenge, because they are merely the customers of BPA’s customers, not direct customers themselves.4 We conclude that APAC has standing to challenge the Settlement, due to the “pass-through” contracts under which its members pay rates that directly reflect the rates BPA charges its direct customers. With respect to the merits, however, we conclude that the Settlement complies with the relevant statutory requirements and with our prior decisions, and we therefore deny APAC’s petition for review.
I. BACKGROUND
We have previously chronicled the history of BPA, a federal agency that markets power generated by federal hydroelectric projects in the Columbia River Basin. See, e.g., Alcoa, Inc. v. Bonneville Power Admin., 698 F.3d 774, 779 (9th Cir.2012); Pac. Nw. Generating Co-op. v. Dep’t of Energy, 580 F.3d 792, 797-800 (9th Cir.2009); Golden Nw., 501 F.3d at 1041; PGE, 501 F.3d at 1013-16; Pub. Power Council, Inc. v. Bonneville Power Admin., 442 F.3d 1204, 1206 (9th Cir.2006); M-SR Pub. Power Agency v. Bonneville Power Admin., 297 F.3d 833, 836-37 (9th Cir.2002) (as amended); Ass’n of Pub. Agency Customers, Inc. v. Bonneville Power Admin., 126 F.3d 1158, 1163-65 (9th Cir.1997) (“APAC”). Nevertheless, because of the complexity of the case, we begin with a brief review of the relevant history of the agency and provisions of the NWPA, one of “the tangle of statutes that govern [BPA’s] operations.” Golden Nw., 501 F.3d at 1042.5 We then discuss the specific facts relevant to this appeal.
A.
Congress created BPA, an agency within the Department of Energy, in 1937. PGE, 501 F.3d at 1013. The agency was initially “tasked with marketing the power generated by federally owned dams on the Columbia River.” Id. For the first thirty years of its existence — from the 1930s through the 1960s — BPA had sufficient resources to meet the power demands of two classes of customers. Id. at 1014. First, BPA provided power to “preference utilities,” also known as “consumer-owned utilities” or “COUs.” This class consists of publicly-owned utilities, cooperatives, and federal agencies, who are accorded priority to federal power under the Bonneville Project Act. Id.; see also 16 U.S.C. § 832c(a), (d). Second, BPA provided power to “non-preference utilities.” PGE, 501 F.3d at 1014. This class of customers is made up of two sub-classes: (1) investor-owned utilities (“IOUs”), who purchase power for resale, and (2) direct service industrial customers (“DSIs”), who purchase power for direct consumption. Id.; see also APAC, 126 F.3d at 1164.
*945As demand for low-cost federal power rose in the 1970s, BPA forecast that it would be unable to meet all of its customers’ power needs by the end of the decade. PGE, 501 F.3d at 1014. An “uncertain and unstable” period followed, during which BPA advised non-preference customers — and, later, preference customers — of its looming inability to provide them with power. APAC, 126 F.3d at 1165; see also PGE, 501 F.3d at 1014. As a result, many non-preference customers were forced to purchase power elsewhere, “at a severe cost disadvantage in the marketplace.” Id.
B.
In response to the pending energy crisis, Congress enacted the NWPA in 1980. The NWPA “transformed BPA from an agency that merely sold whatever power was available from generating facilities in the Federal Columbia River Power System to one charged with the responsibility of meeting the region’s future power needs.” APAC, 126 F.3d at 1165. Of particular importance here, the statute authorizes BPA to “exercise greater control over its power supply and to augment that supply by purchasing electric power in the market.” PGE, 501 F.3d at 1014. It also authorizes the BPA Administrator to “establish and revise the rates at which BPA’s power is sold,” and — subject to certain limitations — to “enter into contracts, agreements, and settlements of claims and contractual obligations.” Id. Two of the provisions granting BPA such authority, section 5, 16 U.S.C. § 839c, and section 7, 16 U.S.C. § 839e, are at issue in this appeal.
1.
Section 5(c) of the NWPA makes low-cost power available to IOUs, one of the classes of non-preference customers. Under this provision, IOUs are entitled to “exchange power they have purchased or generated for lower-cost power generated by BPA.” PGE, 501 F.3d at 1015; see also 16 U.S.C. § 839c(c)(l); Golden Nw., 501 F.3d at 1047. This process, known as the Residential Exchange Program (“REP”), “essentially acts as a cash rebate to the IOUs,” allowing the IOUs to benefit from BPA’s low rates even when BPA cannot itself provide them with power. PGE, 501 F.3d at 1015 (explaining that the “ ‘exchange’ is a paper transaction”).6 The IOUs, in turn, are required to pass on this financial benefit to their customers. 16 U.S.C. § 839c(c)(3); see also Cal. Energy Res. Conservation & Dev. Comm’n v. Johnson, 807 F.2d 1456, 1460 (9th Cir.1986) (explaining that without the REP, “consumers living in areas served by private utilities faced higher power prices than consumers living in areas served by public utilities”).
The traditional formula for deciding if an IOU is entitled to a “REP Benefit” is as follows: first, the IOU offers to sell power to BPA at its “average system cost” (“ASC”) for producing power.7 Second, *946BPA calculates the “PF Exchange rate,” which is the sum of a base rate for power, see 16 U.S.C. § 839e(b)(l), plus any supplemental charges triggered by the “rate ceiling,” see id. at (b)(3), discussed infra. If the PF Exchange rate is lower than the ASC, the IOU is entitled to a REP Benefit, which will be the difference between those two amounts, multiplied by the IOU’s residential load. See 16 U.S.C. § 839c(c)(l) (stating that the Administrator “shall acquire by purchase such power and shall offer, in exchange, to sell an equivalent amount of electric power” (emphasis added)); ROD 2.
2.
While section 5 provides low-cost power to the IOUs, section 7 ensures that the preference customers — i.e., the COUs— will not bear the cost of this benefit. See PGE, 501 F.3d at 1015 (“The legislative history of the NWPA suggests that Congress viewed the NWPA as a compromise between the preference and non-preference utilities”). Section 7 governs the rates that BPA charges its customers, Golden Nw., 501 F.3d at 1041, and it contains two relevant restrictions.
First, BPA may not charge its preference customers higher rates than it would in the absence of the REP. 16 U.S.C. § 839e(b)(2)(C).8 In order to ensure this does not happen, BPA is required to perform a “rate test,” through which it compares the “PF Public rate”— i.e. the projected rate for the COUs — to a hypothetical rate based on five assumptions, including the assumption that no exchanges were made through the REP. Id. at (A)-(E). If the “rate test” shows that the PF Public rate is higher than the hypothetical rate, BPA must adjust the PF Public rate downward by the amount of the difference. This is called the “rate ceiling” trigger.
The triggering of the “rate ceiling” leads to the second restriction: if the PF Public rate is adjusted downward, the cost of making such an adjustment must be recovered from all of the other rates BPA charges for power, including the PF Exchange rate that BPA sets for the IOUs. Id. at (b)(3). This brings us somewhat full circle: the practical effect of adding a supplemental charge to the PF Exchange rate charged to IOUs is simply a reduction in REP Benefits for the IOUs. See PGE, 501 F.3d at 1015.
C.
Put simply, the REP is complicated. It was the source of, “almost continuous litigation” in the 1980s, during which period many IOUs chose to settle with BPA rather than actively participate in the program. ROD 5; see also Cal. Energy Res. Cons. & Dev. Comm’n v. Johnson, 807 F.2d 1456, 1458 (9th Cir.1986). And it was at the heart of the 2000 REP Settlement Agreement, which this court struck down in PGE and Golden Northwest.
In the 2000 REP Settlement Agreement, BPA attempted to settle its REP obligations to the IOUs for fiscal years 2002-2011. Golden Nw., 501 F.3d at 1047. It *947then adjusted the rates for the COUs upward, in order to recover the costs associated with the settlement. Id. at 1048. We held that BPA’s actions were contrary to the NWPA. In PGE, we held — contrary to BPA’s argument — that BPA must comply with sections 5 and 7 “whenever [it] engages in a purchase and exchange of power,” including in settlement agreements. 501 F.3d at 1032 (emphasis added). We concluded that BPA had failed to do so, because the settlement did not rely on the IOUs’ current ASCs — that is, the rates at which the IOUs offer to sell power to BPA — when calculating their REP settlement benefits. Id. at 1033; see also id. at 1037 (concluding that the settlement did not “resemble the REP program created in §§ 5(c) and 7(b) that it purports to be settling”).9 And in PGE’s companion case, Golden Northwest, we further held that it was a violation of section 7(b) for BPA to distribute the costs of the settlement to its preference customers. 501 F.3d at 1048. We remanded both cases to BPA to set rates in accordance with our opinions.
On remand, BPA initiated proceedings to set new rates in compliance with PGE and Golden Northwest. This resulted in several final decisions: (1) the “WP-07 Supplemental Record of Decision,” which set a refund schedule for past over-charges from the unlawful 2000 settlement, (2) the “2008 Residential Purchase and Sale Agreement Record of Decision,” which applied specifically to IOUs, and (3) the' ‘WP-10 Record of Decision,” which established future rates for 2010-2011. The details of these decisions do not matter here. What does matter is that each of these decisions resulted in an onslaught of appeals to this court, which have been stayed pending -the outcome of this case. ROD 29.
D.
Against this backdrop, we turn to the subject of this appeal: the REP-12 Record of Decision. In the face of “seemingly endless litigation” over the REP, a large number of BPA’s customers entered into settlement negotiations.10 This resulted in the REP-12 Settlement Agreement, which was signed by parties representing 94 percent of the total load that BPA serves.11 The Settlement was then submitted to the BPA Administrator,:who conducted a seven-month evaluation to determine if it was reasonable and if it complied with BPA’s statutory mandates, as well as with PGE and Golden Northwest. After concluding that the Settlement was lawful and reasonable, the BPA Administrator adopted it and committed BPA to abide by its terms. ROD 419. The REP12 Record of Decision replaces the Administrator’s previous REP-related decisions. See ROD 20; 29.
Although the Settlement includes “many complicated formulas and terms,” ROD 29, its three key elements can be described succinctly. First, the Settlement sets a *948lump sum of REP benefits to be paid to the IOUs as a class over the seventeen-year term of the settlement.12 These lump sums are broken down by year — for example, in FY 2012, the IOUs will collectively be paid $182.1 million, and in FY 2028, they will collectively be paid $286.1 million. ROD 30. Although the yearly lump sums are fixed, the payments to any particular IOU are not. Rather, the individual IOUs will still be required to file their ASCs with BPA every two years. Pursuant to section 5(c), if an IOU’s ASC does not exceed the applicable exchange rate for a particular period, that IOU will not receive REP benefits for that period.13 The BPA Administrator, in his analysis of the Settlement, concluded that the net present value of the REP benefits under the Settlement — $2.05 billion — is approximately $1 billion less than the net present value of the projected REP benefits over the same period of time, should BPA continue to pay out REP benefits without the Settlement. ROD 59.
Second, the Settlement sets a new “rate test” methodology to meet the requirements of section 7(b). Under its traditional approach, BPA conducts a “rate test” every two years to determine the rate ceiling (i.e. the maximum rate that can be charged to COUs) and the PF Exchange rate. See 16 U.S.C. § 839e(b)(2). But under the Settlement, BPA prospectively conducted the rate test for each year of the Settlement. Thus, it ran seventeen separate rate tests, under which it determined the prospective cost of REP benefits (and the rate ceiling) for fiscal years 2012-2028, should the Settlement not take effect. In addition, it ran these tests using twenty-six different scenarios, to account for a range of different rate levels and litigation outcomes in the absence of the Settlement. BPA then compared the projected cost of REP benefits under these rate tests to the cost of REP benefits under the Settlement. It concluded that the COUs’ interests were adequately protected, because in twenty-three of the twenty-six scenarios, the Settlement results in lower rates for the preference customers than would be allowed by the section 7(b)(2) rate ceiling absent the Settlement.14
Third, the Settlement provides a schedule of refunds to the COUs, who were overcharged under the terms of the 2000 REP Settlement Agreement. See Golden Nw., 501 F.3d at 1048. The Settlement provides that the COUs can retain the refunds they have already received from BPA — which total $587 million, for the period fiscal years 2008-2011 — without further dispute.15 It also provides that BPA will continue to refund the COUs during fiscal years 2012-2019, paying a total of $612 million over the course of eight years. ROD 253. The mechanism for making these refunds is to withhold a certain amount of the IOUs’ REP benefits, which *949the IOUs have agreed can be used to “pay for” the refunds to which the COUs are entitled.
E.
APAC is an “unincorporated ad hoc organization.” It is composed of six member groups, all of whom own and operate industrial facilities in the Pacific Northwest.16 The member groups are not customers of BPA; rather, they purchase electricity from BPA’s preference customers, the COUs. On appeal, APAC submitted an affidavit from the director of energy procurement at Georgia-Pacific LLP (“GP”), stating that GP contracts to buy power from two different COUs, the Clatskanie Public Utility District (“CPUD”) and the Central Lincoln Public Utility District (“CLPUD”).17 The affidavit describes the contractual relationship between GP and CPUD as follows:
The electrical contract between BP and CPUD is a cost-based pass-through contract according to which GP buys power from CPUD at CPUD’s cost to purchase the power from BPA and other sources, plus additional charges for overhead. Thus the rates and charges incurred by
CPUD to purchase power from BPA for the Wauna mill are recovered by GP. The affidavit describes GP’s contractual relationship with CLPUD in nearly identical terms.18 As a result of these “pass through” contracts, GP claims to be “directly impacted financially by any rate increases or decreases adopted by BPA.”
II. JURISDICTION AND STANDARD OF REVIEW
A. Standing
We have jurisdiction to review the REP-12 Record of Decision, because it is a final agency action. See 16 U.S.C. § 839f(e)(5); PGE, 501 F.3d at 1023. At the outset, however, we must address an important threshold question: does APAC, a group whose members are not direct customers of BPA, have standing to challenge the Settlement? Our answer to this question requires two separate inquiries. First, we ask if at least one of APAC’s members has “suffered sufficient injury to satisfy the ‘case or controversy’ requirement of Article III.” Cetacean Cmty. v. Bush, 386 F.3d 1169, 1174 (9th Cir.2004). Second, if APAC has established Article III standing, we “ask whether a statute has conferred ‘standing’ on [at least one of *950APAC’s members],” id. at 1175, such that the member is “within [its] zone of interests,” thereby meeting the requirements for prudential standing, Cent. Ariz. Water Conservation Dist. v. U.S. E.P.A., 990 F.2d 1531, 1538 (9th Cir.1993).19 We conclude that APAC has met the requirements for both constitutional and prudential standing, for the reasons explained below.
1. Constitutional Standing
The requirements for Article III standing are familiar. First, the petitioner must show that it has suffered “an injury in fact,” i.e., “an invasion of a legally protected interest which is (a) concrete and particularized, and (b) actual or imminent, not conjectural or hypothetical.” Lujan v. Defenders of Wildlife, 504 U.S. 555, 560, 112 S.Ct. 2130, 119 L.Ed.2d 351 (1992) (quotation marks and citations omitted). Second, it must show that the injury is “fairly traceable to the challenged action of the defendant,” and is not “the result of the independent action of some third party not before the court.” Id. (quotation marks and alternations omitted). Finally, “it must be likely, as opposed to merely speculative, that the injury will be redressed by a favorable decision.” Id. at 561, 112 S.Ct. 2130 (quotation marks omitted). We' address each requirement in turn, focusing on whether it has been satisfied by one of APAC’s members, GP.
a. Injury in Fact
The alleged injury in this case is economic: according to APAC, its members will “suffer the burden” of over-inflated power rates, which BPA will set in order to ensure it can make the required REP payments to the IOUs.20 Put another way, the Settlement will cause BPA to set higher rates for the COUs, who will in turn set higher rates for members of APAC. The intervening IOUs counter that “because APAC’s members’ rates are set by COUs, not BPA, they have no legal right to any particular rate under the NWPA,” and thus do not have a legally protected interest in non-inflated rates.21 We disagree.
First, we must clarify that a petitioner’s “legally protected interest” need not be a statutorily created interest.22 Thus, to the *951extent the parties and the dissent focus on whether APAC’s members have a “right to any particular rate under the [NWPA],” Dissent at 973, their focus is too narrow.23 We have previously held that “economic injury is generally a legally protected interest.” Cent. Ariz., 990 F.2d at 1537; see also Montana Shooting Sports Ass’n v. Holder, 727 F.3d 975, 980 (9th Cir.2013) (“The economic costs of complying with a licensing scheme can be sufficient for standing.”); San Diego Cnty. Gun Rights Comm. v. Reno, 98 F.3d 1121, 1130 (9th Cir.1996) (“Economic injury is clearly a sufficient basis for standing.”); Aluminum Co. of Am. v. Bonneville Power Admin., 903 F.2d 585, 590 (9th Cir.1989) (“There is harm in paying rates that may be excessive .... ”). And we have found standing where the petitioners’ economic interest in an agency’s action was created by contract, rather than by statute.24 Cent. Ariz., 990 F.2d at 1537-38.
For example, in Central Arizona — a case with strikingly similar facts — the EPA had promulgated a rule requiring the owners of a power generating system to take steps to reduce its S02 emissions. Id. at 1533-34. The petitioners, who purchased electricity from those owners, claimed “an economic interest in the Final Rule,” arguing that they “[would] be required, due to [their] contractual relationship with the [owners], to repay a major portion of ... the costs of installing and maintaining the emission controls required by the Final Rule.” Id. at 1534. We held that the petitioners had standing to sue EPA, concluding, in part, that their pecuniary injury was “clearly a sufficient basis” upon which to establish an “injury in fact,” as required by Lujan,25 Id. at 1537 (quotation marks omitted).
*952Likewise, in Maricopa-Stanfield Irrigation and Drainage District v. United States, we held that the plaintiffs had established “injury in fact” when the alleged unlawful act deprived them of rights they held under contract, not by statute. 158 F.3d 428, 435 (9th Cir.1998). There, the plaintiffs were irrigation districts who claimed that the San Carlos Apache Tribe Water Rights Settlement Act of 1992 (the “SCAT Act”) had resulted in the government taking their rights to certain water without just compensation. Id. at 433. We concluded that the plaintiffs had standing to bring the lawsuit, explaining in part: Id. at 434 (emphasis added). Here, as in Central Arizona and Maricopa-Stanfield, GP has an interest in receiving whatever it is guaranteed under its contracts with the COUs. By alleging that the Settlement will directly affect the rates it is charged, resulting in economic harm, GP has sufficiently established an invasion of a legally protected interest.26
The Districts allege that, by reallocating the excess Ak-Chin water to the [Central Arizona Project], the Ak-Chin Settlement Act automatically reallocated that water to the non-Indian agricultural pool, which water the Districts had purchased under their 1984 subcontracts. If the Districts are correct in their assertion that the excess Ak-Chin water [should have] defaulted to them, then the SCAT Act’s reallocation of the excess Akr-Chin water ... indirectly deprived the Districts of water due to them in their subcontracts. Because a higher-priority right to a CAP water allocation is more valuable than a lower-priority right to the same water, the Districts adequately have alleged that the SCAT Act deprived them of their legal rights to the excess Ak-Chin water allocation.
But our inquiry does not end there. GP still must show that its harm is “concrete and particularized” and “actual or imminent, not conjectural or hypothetical.” Lujan, 504 U.S. at 560, 112 S.Ct. 2130 (quotation marks omitted). The COUs argue that GP cannot meet these requirements, because APAC’s members are not entitled to “any particular rate under the NWPA.” We disagree.
The record shows that the “pass-through” contracts are just what their name suggests: under these contracts, GP’s affidavit explains, GP “buys power from [the COUs] at [the COUs’] cost to purchase the power from BPA,” such that “the rates and charges incurred by [the COUs] to purchase power from BPA ... are recovered from” GP. Thus, BPA’s argument that “any burden imposed on APAC’s members comes from the COUs that sell power to them,” and not from BPA, relies on technicalities at the expense of common sense. Under the terms of the Settlement, GP will almost certainly be charged a rate that directly reflects the rates BPA charges the COUs. See Clapper *953v. Amnesty Int’l USA, — U.S.-, 133 S.Ct. 1138, 1150 n. 5, 185 L.Ed.2d 264 (2013) (“Our cases do not uniformly require plaintiffs to demonstrate that it is literally certain that the harms they identify will come about”). Although “the extent of [GP’s] economic harm is not readily determinable,” Cent. Ariz., 990 F.2d at 1538 (emphasis added), the record reveals that if APAC prevails on the merits of its claims, “the [Settlement] will likely cause [GP] some amount of pecuniary harm,” id., due to the pass-through provisions in its contracts. See Maricopa-Stanfield, 158 F.3d at 434 (“If the SCAT Act reallocated water that became the Districts’ property under the Ak-Chin Settlement Act, then the harm is certain even though its precise valuation may not be.”); see also Bennett v. Spear, 520 U.S. 154, 168, 117 S.Ct. 1154, 137 L.Ed.2d 281 (1997) (“Given petitioners’ allegation that the amount of available water will be reduced and that they will be adversely affected thereby, it is easy to presume specific facts under which petitioners will be injured .... ”). We therefore conclude that the evidentiary showing by APAC is sufficient to establish an actual, concrete harm that is neither conjectural nor hypothetical. See Lujan, 504 U.S. at 560, 112 S.Ct. 2130.
b. Fairly Traceable to Actions of BPA
We next turn to the second requirement for constitutional standing: that the alleged injury be “fairly traceable to the challenged action of the defendant,” rather than to “the independent actions of some third party not before the court.” Id. (alterations and quotation marks omitted). To satisfy this requirement, APAC need not show that BPA’s actions are “the very last step in the chain of causation.” Bennett, 520 U.S. at 169, 117 S.Ct. 1154. Rather, APAC must show only that there are no independent actions of third parties that break the causal link between BPA’s allegedly unlawful act — i.e., its adoption of the Settlement — and GP’s economic harm. If there are no such independent actions, BPA’s challenged actions may be understood to have had a “determinative ... effect upon the action” of the third party, which in turn will cause harm to GP. Id.; see also Maya v. Centex Corp., 658 F.3d 1060, 1070 (9th Cir.2011) (“A causal chain does not fail simply because it has several ‘links,’ provided those links are ‘not hypothetical or tenuous’ and remain ‘plausible.’ ” (quoting Nat’l Audubon Soc., Inc. v. Davis, 307 F.3d 835, 849 (9th Cir.2002)) (internal alteration omitted)).
Here, again, we find guidance in Central Arizona. As we explained there, the fact that the petitioners’ “contractual obligations may provide the basis for its economic liability for the increased costs imposed by the Final Rule ... hardly means that the Final Rule itself is not the direct cause of that liability.” 990 F.2d at 1538. This statement rings even more true here, where the pass-through contracts directly pass on to GP whatever rates BPA charges the COUs. Indeed, it is difficult to imagine a causal chain in which the defendant’s actions are more “determinative” of the actions of a third party — and, in turn, of the alleged harm done to GP. See Bennett, 520 U.S. at 169, 117 S.Ct. 1154. To consider the COUs’ rate-setting an “independent action,” separate from BPA’s rate-setting, simply “misses the point.” Cent. Ariz., 990 F.2d at 1538. Nor does it matter, as the dissent suggests, that the COUs may be able to depart from their contractual arrangements with ■ APAC members. See Dissent at 976-77. This does not change the fact that the contractual rates GP will pay are directly correlated to the Settlement Agreement. We therefore conclude that APAC has shown that GP’s alleged economic injury is “fairly *954traceable” to the challenged action of BPA — i.e., the adoption of the Settlement — such that its has satisfied the second requirement for Article III standing.
c. Redressability
Finally, we consider the third requirement for Article III standing: “it must be likely, as opposed to merely speculative, that the injury will be redressed by a favorable decision.” Lujan, 504 U.S. at 561, 112 S.Ct. 2130 (quotation marks omitted). We conclude that GP has satisfied this requirement for the same reasons it has satisfied the “fairly traceable” causation requirement. If the Settlement turned out to be unlawful, we would invalidate the REP12 Record of Decision; as a result, it could no longer be the source of any economic harm to GP. GP has therefore satisfied the third requirement for Article III standing, and as a result, we conclude that APAC has constitutional standing to challenge the Settlement.
2. Prudential Standing
We turn to the second standing inquiry: the “judicially self-imposed” requirement of prudential standing.27 “For a plaintiff to have prudential standing under the APA, the interest sought to be protected by the complainant must be arguably within the zone of interests to be protected or regulated by the statute in question.” Nat’l Credit Union Admin. v. First Nat. Bank & Trust Co., 522 U.S. 479, 488, 118 S.Ct. 927, 140 L.Ed.2d 1 (1998) (internal quotation marks and alteration omitted); see also Cetacean Cmty., 386 F.3d at 1176 (‘When a plaintiff seeks to challenge federal administrative action, section 10(a) [of the Administrative Procedure Act (‘APA’)] provides a mechanism to enforce the underlying substantive statute.”).28 To satisfy this requirement, “all that is required is a rough correspondence of the plaintiffs interests with the statutory purpose.” Bernhardt v. Cnty. of Los Angeles, 279 F.3d 862, 870 (9th Cir.2002). The test “ ‘is not meant to be especially demanding’ ... keeping with Congress’s ‘evident intent’ when enacting the APA ‘to make agency action presumptively reviewable.’ ” Match-E-Be-Nash-She-Wish Band of Pottawatomi Indians v. Patchak, — U.S. -, 132 S.Ct. 2199, 2210, 183 L.Ed.2d 211 (2012) (quoting Clarke v. Se*955curities Industry Assn., 479 U.S. 388, 399, 107 S.Ct. 750, 93 L.Ed.2d 757 (1987)); see also id. (noting that “the benefit of any doubt goes to the plaintiff’).
Here, the interests of APAC’s members clearly line up with the statutory purposes of the NWPA.29 APAC’s members have an interest in purchasing low-cost power, which allows them to operate their businesses. The statute, in turn, states that one of its purposes is “to provide that the customers of the [BPA] and their consumers continue to pay all costs necessary to produce, transmit, and conserve resources to meet the region’s electric power requirements.” 16 U.S.C. § 839(4) (emphasis added); see also 16 U.S.C. § 838g (explaining that “rate schedules ... shall be fixed and established ... with a view to encouraging the widest possible diversified use of electric power at the lowest possible rates to consumers consistent with sound business principles” (emphasis added)); § 839a(5) (defining “consumer” as “any end user of electric power”). The legislative history of the NWPA also shows that Congress intended for the customers of COUs to benefit from its protections. See H.R.Rep. No. 96-976, pt. 2, at 36 (1980), reprinted in 1980 U.S.C.C.A.N. 6023, 6034 (“As an added protection against preference utilities and their customers suffering adverse economic consequences as a result of this legislation, section 7(b)(2) establishes a ‘rate ceiling.’ ” (emphasis added)). On this basis, we conclude that the interests of APAC’s members are more than “marginally related” to the purposes of the NWPA, and therefore they have satisfied the requirements for prudential standing. See Match-E-Be-Nash-She-Wish, 132 S.Ct. at 2210.
In sum, we conclude that APAC has constitutional and prudential standing to challenge the Settlement. We therefore turn to the merits of the petition for review.
B. Standard of Review
“Our review of BPA’s actions is governed by the [APA].” PGE, 501 F.3d at 1023; see also 16 U.S.C. § 839f(e)(2). Thus, we will set aside the Record of Decision only if it is “arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law.” 5 U.S.C. § 706(2)(a). “In determining whether BPA has acted in accordance with law, we defer to BPA’s reasonable interpretations of its governing statutes.” Golden Nw., 501 F.3d at 1045; see also Confederated Tribes of Umatilla Indian Reservation v. Bonneville Power Admin., 342 F.3d 924, 928 (9th Cir.2003) (“Due to the complex subject matter and BPA’s factual and legal expertise, we give special, substantial deference to BPA’s interpretation of the [NWPA].”).
III. ANALYSIS
A. NWPA Section 5(c)
One of APAC’s main arguments is that the Settlement does not comply with see*956tion 5(c) of the NWPA, which governs the process by which BPA implements the REP. See 16 U.S.C. § 839c(c). First, APAC argues that setting a lump sum of REP benefits, rather than calculating REP benefits “on an individual IOU-by-IOU basis,” violates section 5(c)(1). Second, APAC argues that BPA’s waiver of the “in lieu” provision of section 5(c), 16 U.S.C. § 839c(c)(5), is unlawful. We conclude that the Settlement does not violate section 5(c) on either ground.
1. Section 5(c)(1)
We begin by clarifying the process for setting REP benefits. This is a three-step process: first, BPA estimates the aggregate amount of REP benefits to be paid to the IOUs for a given year, pursuant to section 7(b)(2); second, BPA uses that estimate to set the PF Exchange rate for a given year; third, BPA uses the PF Exchange rate to determine an individual IOU’s REP Benefit, pursuant to section 5(c)(1). Thus, contrary to APAC’s characterization of the process, BPA must always calculate the aggregate amount of REP benefits to be paid out in a given year prior to setting the PF Exchange rate for that year. See 16 U.S.C. § 839e(b)(2)(C). This is not a novel concept invented by the Settlement. As the BPA Administrator explained, “[i]f BPA does not know the total permissible cost of the REP after running the 7(b)(2) rate test, then BPA has no way of setting the PF Exchange rate.” ROD 93.
What is a novel concept is that the Settlement obligates BPA to actually pay out the total amount of REP benefits it estimates under section 7(b). Put another way, estimating the aggregate amount of REP benefits to be paid is fundamentally different from actually setting that amount. We acknowledge that this is an important difference. But we fail to see how setting an aggregate amount of REP benefits is a violation of section 5(c), so long as the amount that is set is less than the maximum possible REP benefits that could be distributed pursuant to section 7. As the BPA Administrator explained, “it is section 7(b) that ultimately establishes the amount of the REP costs that BPA may recover in rates, while section 5(c) ... establishes how the REP benefits are distributed among the REP participants.” ROD 93 (emphasis added). We find this explanation helpful, as it clearly isolates what we must decide here: so long as the amount of REP benefits under the Settlement is lawful — a question we address infra in Part III.B — all that we must decide is whether the process for setting and distributing those benefits among the individual IOUs complies with section 5(c).
a. Setting REP Benefits for Individual IOUs
We therefore turn to section 5(c). Under this provision, there are two requirements that BPA must follow when setting REP benefits for any given IOU. First, “the Administrator shall acquire by purchase” the power that a utility “offers to sell ... at [its] average system cost [ASC].” 16 U.S.C. § 839c(c)(l). Second, “the Administrator shall ... sell an equivalent amount of power to such utility” in return. Id. As APAC reads section 5(c), these two directives necessarily require BPA to calculate an individual IOU’s REP Benefit using the following formula, which we will call the “traditional section 5 formula”:
[ (ASC-PF Exchange Rate) x (load) ] = REP Benefit
Thus, according to APAC, section 5(c) requires BPA to first calculate the PF Exchange rate, and then — on the basis of that rate, together with an IOU’s ASC and *957load — calculate the IOU’s REP Benefit.30 But by setting a lump sum of REP benefits, APAC argues, the Settlement allows BPA to “back[ ] into the rate[ ] to produce [the] guaranteed REP benefits.” APAC claims that this is a violation of section 5(c).
We disagree. Although the traditional section 5 formula satisfies the requirements of section 5(c), it is not the only formula that would do so. Of critical importance here, section 5(c) does not specify the rate at which BPA must sell power back to qualifying utilities; as the Administrator noted, “[s]ection 5(c) is notably silent on what rate BPA must use to sell its power to the utility.” ROD 93. Thus, although BPA has traditionally calculated the REP Benefit using the PF Exchange rate, all that section 5 actually requires is for BPA to make the following calculation, where both italicized terms are variables:
[ (ASC-Rate Charged by BPA) x
(load) ] = REP Benefít
If BPA uses this basic formula with the goal of calculating the maximum REP benefit for any given IOU, it will effectively use the traditional section 5 formula— that is, it will figure out the PF Exchange rate, and it will base the REP Benefit on that rate. How do we know this? We know because the PF Exchange rate is the sum of BPA’s base rate for power, 16 U.S.C. § 839e(b)(l), plus any supplemental charges triggered by the “rate ceiling,” id. at (b)(3). Thus, the PF Exchange rate is the lowest rate that BPA can charge the IOUs. And, as the lowest rate possible, it necessarily creates the largest possible difference with the ASC — which, in turn, re-suits in the maximum possible REP Benefit.
But an IOU does not have to accept the maximum possible REP Benefit. See, e.g., United States v. Mezzanatto, 513 U.S. 196, 201, 115 S.Ct. 797, 130 L.Ed.2d 697 (1995) (“[A]bsent some affirmative indication of Congress’ intent to preclude waiver, we have presumed that statutory provisions are subject to waiver by voluntary agreement of the parties.”). We agree with the Administrator that the IOUs are not prohibited from “taking fewer REP benefits than any otherwise would be entitled to under the law.” ROD 91. And if an IOU accepts less than the maximum REP Benefit, the effect is simply that BPA will charge a higher rate to that IOU, in order to create a smaller difference between the ASC and the rate charged. Nothing in section 5 suggests that this is unlawful. See ROD 119 (concluding that “allowing the IOUs to waive their statutory rights to full REP benefits ... results in lower rates for all COU ratepayers”). We therefore conclude that setting a predetermined REP Benefit, as required by the Settlement, is not a violation of section 5 so long as the pre-determined benefit is lower than the maximum REP Benefit that would result from using the PF Exchange rate.31 See 16 U.S.C. § 839e(b)(2) (stating that the rates charged to the COUs “may not exceed” a certain rate, but not setting a minimum rate); see also ROD 94 (“Section 7(b)(2) creates only a cap — not a floor — on the aggregate amount of REP benefits that BPA must pay to the exchanging utilities and include in rates.”).32 Here, the BPA *958Administrator concluded that the pre-determined REP benefits under the Settlement amount to approximately $1 billion less than what the IOUs would be entitled to without the Settlement, and therefore setting such a lump sum is not a violation of section 5(c)(1).
b. Distributing REP Benefits Among the IOUs
Our inquiry could end there if we knew that every IOU would qualify for REP benefits for each of the seventeen years covered by the Settlement. If so, it would logically follow that no IOU could receive REP benefits beyond what they would be entitled to in the absence of the Settlement.33 But here, it is not a foregone conclusion that every settling IOU will qualify for REP benefits in a given year. Rather, under the Settlement, each IOU is required to file its ASC with BPA every two years, consistent with BPA’s current methodology. ROD 111. BPA will then determine if the IOU qualifies for REP benefits by comparing the IOU’s ASC to the “utility-specific exchange rate” established for that IOU. ROD 112. If the ASC is higher than the “utility specific exchange rate,” BPA will calculate the IOU’s REP benefits using the following formula, set forth in section 6 of the Settlement:
([ (ASC - Base Rate) x (load) ] x [ (Total REP Settlement Benefits) -e (2((ASC - Base Rate) x Load)) ]) + 6.2 Adjustment = REP Benefit
ROD Appendix A 19-20; see also ROD 376-77. Although complicated, this formula essentially serves one main purpose: it ensures that each qualifying IOU will receive an amount of REP benefits proportional to the difference between its ASC and the base rate for power.34
*959APAC argues that it is unlawful for BPA to use a “formula not specified in the statute,” for two reasons: first “BPA cannot assure that it will pay REP benefits only to those qualified IOU’s that qualify for such a benefit,” and second, it cannot assure that it will pay REP benefits “only in the amount to which each qualified IOU is entitled under § 5(c).”
With respect to APAC’s first argument, we agree that some IOUs could qualify for REP benefits under the Settlement even though they would not qualify for benefits absent the Settlement. The formula used in the Settlement requires BPA to calculate only “(ASC - Base Rate) x (Load),” as opposed to “(ASC - PF Exchange Rate) x (Load),” when deciding if an IOU qualifies for benefits. Because the base rate for power is necessarily lower than the PF Exchange rate, the former formula will allow more IOUs to qualify for REP benefits than the latter formula.35
But this is not unlawful. Although BPA has traditionally calculated REP benefits using the PF Exchange rate, section 5(c) does not prohibit BPA from selling power to the IOUs at rates lower than the PF Exchange rate. See ROD 94 (“Section 7(b)(2) does not require BPA to either pay the IOUs or charge the COUs in rates the exact amount of REP benefits established by a comparison of the utilities’ ASCs and BPA’s PF Exchange rate.”). Rather, under its traditional approach,' BPA has done so in order to ensure that the COUs’ interests are protected under section 7. But once BPA has fulfilled its obligations under section 7, as it has under the Settlement,36 section 5 does not impose any additional restrictions on the rate at which BPA must sell power to the IOUs. See ROD 115 (“Aggregate REP costs are determined pursuant to sections 7(b)(1) and 7(b)(2) of the Northwest Power Act. Once the size of the aggregate REP is determined, BPA will use ASCs, PF Exchange rates, and qualifying exchange load to determine each utility’s REP benefits, whether under the Settlement or under no settlement.”). Thus, even though more IOUs may qualify for REP Benefits under the Settlement than otherwise would qualify, the formula that BPA uses to determine eligibility still complies with section 5.
The same reasoning leads us to reject APAC’s second argument, that some IOUs may receive a greater share of REP bene*960fits than they are “entitled” to under section 5(c). Yet again, we agree with the factual premise of APAC’s argument: if the total amount of REP benefits is a pie, and not every IOU gets a slice of the pie, the other IOUs will simply get corresponding bigger slices of pie.37 Or, as APAC frames it, “each qualifying IOU will receive its proportional share of the fixed total annual amount of REP benefits provided in the Settlement regardless of the actual difference between its ASC and Exchange Rate.” And we understand the intuitive concern that a particular IOU should not receive greater benefits under the Settlement than it would otherwise.
But here, again, we conclude that so long as the total amount of REP benefits distributed does not violate section 7, there is no statutory restriction on what share of those benefits any particular IOU may receive. As the Administrator explained, if “the IOUs wish to share among themselves a smaller amount of REP benefits through a fixed payment stream that settles future uncertainties ... there is nothing in section 5(c) ... that prohibits BPA from honoring such a decision.” ROD 94. Thus, so long as “the aggregate level of REP benefits provided under the Settlement” comports with section 7, and “the distribution of those payments is being administered in a manner that closely resembles the REP envisioned by Congress in section 5(c),” the Settlement is “consistent with BPA’s statutory authority and is consistent with law.” ROD 115; see also PGE, 501 F.3d at 1037 (striking down the 2000 Settlement because it did not “resemble” the REP program created in section 5). And given the meticulous calculations that BPA will use to distribute the REP benefits proportionately among the IOUs, we too are “frankly at a loss as to how the Settlement ... could be closer to the[ ] statutory requirements” of section 5(c).38 ROD 115. We therefore agree with the Administrator that the Settlement’s lump sum of REP benefits does not violate section 5(c)(1). See Chevron, U.S.A., Inc. v. Natural Res. Def. Council, Inc., 467 U.S. 837, 843, 104 S.Ct. 2778, 81 L.Ed.2d 694 (1984).
2. Section 5(c)(5) (“in lieu” powers)
We also reject APAC’s argument that BPA violated section 5(c) by waiving its ability to make in lieu purchases pursuant to section 5(c)(5). See 16 U.S.C. § 839c(c)(5).39 The in lieu provision of section 5 permits BPA, “in its discretion, [to] sell the IOUs actual power purchased from other sources in lieu of participating in the REP so long as BPA’s cost for purchasing such power is less than the IOUs’ cost to produce or secure their own power.” PGE, 501 F.3d at 1022. Thus, in theory, BPA can reduce the costs of the REP by engaging in in lieu transactions, which involve the actual sale of power, *961rather than paper transactions.40 We agree with the BPA Administrator’s conclusion that BPA did not violate section 5(c) by waiving this authority. See ROD 129-34.
First, we agree with the Administrator that BPA’s decision to engage, or not engage, in in-lieu transactions is entirely discretionary. See ROD 133. Indeed, the statute itself says only that BPA “may” engage in in-lieu transactions. 16 U.S.C. § 839c(e)(5) (emphasis added). “The permissive language and the absence of any legislative history lead us to conclude that the implementation of section 5(c)(5) is completely within the discretion of the BPA.” Cal. Energy, 807 F.2d at 1462. Thus, the Administrator has interpreted section 5 as presenting “no statutory impediment” to BPA’s waiving its in-lieu authority, so long as BPA provides “a reasoned decision for withholding [its] discretion under the Settlement.” ROD 131; see also ROD 133 (explaining that the “discretionary decision to engage in in-lieu transactions,” pursuant to section 5(c)(5), is not “part of BPA’s obligation to protect the rates of COUs under section 7(b)(2)”).
This is not to say that it is always permissible for BPA to waive its in-lieu authority. As APAC points out, we have previously held — albeit under markedly different facts — that BPA would have “abused its discretion under 5(c)(5)” if it had “completely precluded itself from ever making in-lieu purchases.” Cal. Energy, 807 F.2d at 1462 (concluding that the petitioner had not shown that the contract actually contained such a “complete ban on in-lieu sales of power”). In California Energy, however, the contracts at issue did not contain any limit on the amount of REP benefits that utilities might receive, meaning that the risk of waiving the in-lieu power — which is a means of keeping REP benefits in check — were much higher than in this case. This is consistent with the Administrator’s observation that “[i]n a world where the IOUs’ REP payments are determined rate case by rate case, it makes sense for the Administrator to retain his rights to engage in in lieu transactions to damper otherwise unknown REP costs.” ROD 130.
Here, unlike in California Energy, there is a cap on the total amount of REP benefits the IOUs can receive under the Settlement, meaning that the cost of REP benefits will not suddenly spike in an unexpected way, as it could absent the Settlement. And BPA has provided a reasoned decision for waiving its in-lieu authority, taking into account the costs and benefits of doing so. Its primary reason for waiving this authority is “to achieve the substantial cost protections afforded by the Settlement,” ROD 130, the certainty of which would be undermined if BPA retained the power to add another variable to its rate calculations. Essentially, BPA has waived one way of controlling REP costs — the ability to engage in in-lieu transactions — for another, greater way of controlling REP costs, i.e., the Settlement. ROD 132-33. We agree with the BPA Administrator that this is a reasonable trade-off. Furthermore, we note that because the amount of REP benefits is set under the Settlement, the only effect of an in-lieu transaction would be to “adjust the amounts paid to each IOU,” as opposed to creating “cost savings to BPA or any other ratepayers.” ROD 131. This further supports BPA’s decision to waive its in-lieu authority, because doing so does not de*962prive other ratepayers of a benefit they might otherwise receive. We therefore conclude that, under these facts, it was reasonable, and not unlawful, for BPA to waive its authority to engage in in-lieu transactions.
We likewise reject APAC’s second argument, that “BPA, as a member of the executive branch,” cannot contract away the powers given to it by Congress. Here, BPA is “acting as a private contracting party,” and as a result, its “rights and duties are governed by law applicable to private parties unaltered by the government’s sovereign status.” Kimberly Assocs. v. United States, 261 F.3d 864, 869 (9th Cir.2001); see also PGE, 501 F.3d at 1029 n. 17 (“Unlike many regulatory agencies, ‘Congress endowed the Administrator with broad-based powers to act in accordance with BPA’s best business interests,’ allowing BPA ‘to function more like a business than a governmental regulatory agency.’ ” (quoting APAC, 126 F.3d at 1170)). BPA therefore did not err by waiving its ability to exercise one of its discretionary powers.
B. NWPA Section 7(b)
APAC also argues that the Settlement does not comply with section 7(b) of the NWPA, under which BPA must calculate a “rate ceiling” to protect the COUs. See 16 U.S.C. § 839e(b)(2)-(3). Here, rather than challenging the “lump sum” term of the Settlement, APAC challenges the new methodology for running the “rate test” under section 7(b). As explained supra, under the Settlement, BPA ran the “rate test” prospectively for each year of the Settlement.
APAC argues that under section 7(b), BPA cannot use rate projections “that extend beyond five years,” and therefore it cannot rely on its prospective rate tests for the entire term of the seventeen-year settlement. In support of this argument, APAC cites to the requirement that BPA must calculate the rate ceiling for any given year using projected power costs for that year, “plus the ensuing four years.” 16 U.S.C. § 839e(b)(2); see also id. at (C) (explaining that BPA must calculate the rate ceiling by assuming that no REP benefits are paid out “during such five-year period”). This requirement, according to APAC, imposes “time constraints ... which were designed to ensure that REP benefits must be based on current cost and load data.” We disagree.
As APAC concedes, section 7(b) is silent with respect to how far in advance BPA can run the rate test for any given year. And the language APAC cites requires only that BPA use information from five separate years — the year in question, plus the following four years — to set rates for a single year. This requirement does not impose a restriction on running the section 7(b)(2) rate test in advance of a particular year; to the contrary, it supports the conclusion that BPA can rely on projected rates when running its rate tests.
In the absence of clear statutory language regarding how far in advance BPA can run its rate tests, we accord substantial deference to BPA’s interpretation of section 7. See PGE, 501 F.3d at 1025. Here, the Administrator concluded that since BPA unquestionably has the legal authority to settle REP disputes, see id. at 1030, it must also be able to satisfy its section 7(b)(2) obligations by running the rate test for the term of the settlement. ROD 173-74. Otherwise, “there could never be a meaningful REP settlement,” or at least not one that settled the dispute for longer than a five-year period. ROD 174. The Administrator thus explained:
*963In a normal ratemaking context, where BPA revises its rates every two years in a contested environment, BPA conducts the 7(b)(2) rate test for the rate period plus four years to determine two-year rates. A REP settlement, however, resolves REP disputes for a longer term than a single rate period.... Therefore a REP settlement must satisfy section 7(b)(2) in a different manner from the rate test used to establish rates for a single rate period.
ROD 173. We conclude that this is a reasonable interpretation of section 7(b)(2). See Chevron, 467 U.S. at 843 & n. 11, 104 S.Ct. 2778 (“[I]f the statute is silent or ambiguous with respect to the specific issue, the question for the court is whether the agency’s answer is based on a permissible construction of the statute. The court need not conclude that the agency construction was the only one it permissibly could have adopted to uphold the construction .... ”). As BPA argues in its answering brief, section 7(b)(2) is not “a straitjacket that effectively prohibits settlement of the REP.” And the mere fact that BPA has traditionally calculated the rate ceiling on a two-year cycle does not mean that is the only legal method for running the test.41 Rather, it makes sense that BPA would run the rate test for ¿ two-year period when setting rates for the upcoming two years, and for a seventeen-year period when setting rates for the upcoming seventeen years.
Nor does BPA’s method of running the section 7(b)(2) rate test under the Settlement render the test “superfluous,” as APAC argues. The purpose of the rate test is not to ensure that BPA charges the COUs the exact amount at which the rate ceiling is set; the purpose is to ensure they are charged an amount no higher than the rate ceiling. See 16 U.S.C. § 839e(b)(2). Thus, contrary to APAC’s argument, it does not matter if “the result of the § 7(b)(2) rate test can be directly, arithmetically linked” to the COUs’ rates, so long as those rates to do not exceed the rate ceiling. The section 7(b)(2) rate test plays an important role in the Settlement, insofar as it requires BPA to compare the lump sum of REP benefits to the projected rate ceilings, in order to ensure that the COUs would not be charged rates higher than the rate ceiling. And to the extent the Settlement “pre-determine[s] the rate ceiling” by setting a lump sum of REP benefits, as APAC argues, it pre-determines a lower rate ceiling than would otherwise be set under section 7(b)(2). This is not a violation of section 7(b)(2).
In addition to challenging the method of applying the section 7(b)(2) rate test, APAC also challenges its result. Thus, it argues that the Settlement violates section 7 because “the projected costs under some of the various scenarios in [BPA’s] analysis did, in fact, exceed the § 7(b)(2) rate test.” It is true that in three of the twenty-six scenarios, the COUs would not receive greater rate protection under the Settlement than they would without the Settlement.42 But these *964three scenarios involved “extreme instance[s] where the COUs prevail on multiple major contested issues and the IOUs succeed in virtually none of their issues.” ROD 59; 198. Although we recognize the narrow possibility that a violation of section 7(b)(3) could occur if one of these scenarios presented itself, we are satisfied with the Administrator’s conclusion that these “extreme” scenarios are unlikely to occur. ROD 80-81. “This is not to say that BPA could act contrary to a clear statutory directive in settling, but if there is room for doubt, we ought not to resolve it in a manner that sends the parties back to litigation.” Util. Reform Project v. Bonneville Power Admin., 869 F.2d 437, 443 (9th Cir.1989). Such is the case here.
C. Cost Recovery Adjustment Clause
APAC next argues that the Settlement is unlawful because it does not permit BPA to apply a Cost Recovery Adjustment Clause (“CRAC”) to the REP benefit levels. The CRAC is a rate mechanism by which BPA can adjust customers’ rates when “changes in costs and revenues vary substantially from what BPA was projecting when setting rates,” so that BPA is able to recover all of its costs. ROD 138; see also Indus. Customers of Nw. Utilities v. Bonneville Power Admin., 408 F.3d 638, 642 (9th Cir.2005) (“The CRACs were created to allow the BPA to address any financial shortfalls without having to raise base rates.”). APAC argues that by “guaranteeing the IOUs a fixed amount of REP benefits that BPA cannot adjust,” the Settlement “excuses IOU customers from the CRAC,” which means that other customers will bear the burden of assuring that BPA recovers its costs. We agree with the factual premise that BPA cannot apply a CRAC to the IOUs’ REP benefit levels under the Settlement, even if BPA’s costs are higher than expected. See ROD 134. We nevertheless reject APAC’s argument, for two reasons.
First, as the BPA Administrator explained “CRACs are not required by the [NWPA].” Rather, they are a mechanism by which BPA exercises its statutory authority to “recover ... the cost associated with the acquisition, conservation, and transmission of electric power.” 16 U.S.C. § 839e(a)(1); see also Cal. Energy Comm’n v. Bonneville Power Admin., 909 F.2d 1298, 1303 (9th Cir.1990) (explaining that section 7 “requires BPA, in marketing federal power, to establish rates that will produce sufficient revenues to ensure BPA’s fiscal independence”). BPA thus has broad authority to determine if and how to apply a CRAC. See, e.g., Pub. Power Council, 442 F.3d at 1211 (explaining that a CRAC is “entirely bound up with BPA’s rate making responsibilities, and we owe deference to the BPA in that area”).
Second, to the extent APAC challenges BPA’s exercise of this discretion, we reject this challenge. The BPA Administrator concluded that it was reasonable to insulate the IOUs from a potential CRAC for two reasons: first, the IOUs “will not receive any upside benefits during a rate period” if, for example, BPA is unexpectedly able to charge lower rates than expected; and second, “because the REP benefits are fixed, the IOUs’ REP benefits payments would never be a contributing factor” to any unexpected costs that might trigger a CRAC. ROD 135; see also ROD 137. Thus, “the lack of a CRAC mecha*965nism in the Settlement ... [is] simply one of the trade-offs” of the Settlement, counter-balanced by other terms that are less beneficial to the IOUs. ROD 136. And while “COU customers may feel the brunt of a CRAC in a future rate case,” the BPA Administrator concluded that “the discount the IOUs are taking in their REP benefits under the Settlement would ... more than make-up for the small amount of CRAC contributions the IOUs would have provided under a no-settlement alternative.” ROD 139. This was a reasonable conclusion. See Pac. Nw. Generating Coop., 580 F.3d at 806 (“[W]e have identified the question of how best to further BPA’s business interests consistent with its public mission as a statutory gap that Congress has left to BPA to fill.” (quotation marks omitted)); Pub. Power Council, 442 F.3d at 1209 (“[W]e may not substitute our own judgment for that of BPA; we must simply assess whether BPA relied on improper factors, failed to consider an important aspect of the question, offered an explanation for its decision that runs counter to the evidence before it, or rendered a decision that is so implausible that it could not be ascribed to a difference in view or the product of agency expertise.” (quotation marks and alterations omitted)). We therefore conclude that the Administrator’s decision to approve the Settlement without including a CRAC mechanism was neither unlawful nor unreasonable.
D. Bonneville Power Act and FERC Regulations
1.
In addition to arguing that the Settlement violates the NWPA, APAC also argues that the Settlement violates the Bonneville Project Act, 16 U.S.C. § 832d, and applicable FERC regulations, 18 C.F.R. §§ 300.1(b)(6), 300.21(e)(1), by setting rates for a period that exceeds five years.43
These sources require that contractual rates be equitably adjusted no less than once every five years. See 16 U.S.C. § 832d(a) (“Contracts entered into under this subsection shall contain ... such provisions as the administrator and purchaser agree upon for the equitable adjustment of rates at appropriate intervals, not less frequently than once in every five years....” (emphasis added)); 18 C.F.R. § 300.1(b)(6) (“Proposed rate approval period means the period for which confirmation and approval of the rate schedules is requested. This period must not exceed five years.”); § 300.21(e)(1) (stating that rate-approval periods are “not to exceed a five-year period” unless FERC deems it appropriate). But, as BPA argues, “establishing costs is not the same as setting rates.” Here, the Settlement sets a fixed amount of REP benefits that BPA will be required to pay over the term of the Settlement, but it does not set any rates, meaning the five-year limit on rate-setting is inapplicable. As the BPA Administrator explained,
Establishing rates and establishing costs are two substantively different things. The Settlement establishes the amount of REP benefits provided to the IOUs over the Settlement term and thus the amount of REP costs included in preference customers’ rates during that term. The Settlement does not establish rates.
ROD 203. Rather, the Settlement resolves disputes about REP costs and rate-making methodology, neither of which *966“must be revised every five years” by statute or regulation. ROD 202.
Furthermore, although the Settlement “pre-determines” REP benefits, that does not mean that it also pre-determines rates. As the Administrator explained, “ratemaking involves many steps, including a forecast of loads and resources; a determination1 of BPA’s total revenue requirement; a forecast of market prices; an analysis of risk and its mitigation; a cost of service analysis; a rate design analysis; and additional steps.” ROD 202. The Settlement itself likewise makes clear that BPA will continue to engage in ongoing rate-setting throughout the term of the Settlement. See, e.g., ROD Appendix A 19 (“For each Fiscal Year, BPA will develop rates, in the Rate Proceeding for the applicable Rate Period, such that each IOU will be paid its IOU-Specific REP Settlement Benefit Amount as calculated for such Fiscal Year pursuant to this section 6.”). Indeed, after the Administrator approved the Settlement, BPA conducted the “BP-12” rate proceeding to “establish[ ] power and transmission rates for FY 2012-2013.” ROD 25. We thus conclude that the Settlement sets only costs, not rates, and therefore does not violate the five-year rate-setting limitations established by the Bonneville Power Act and FERC regulations.
2.
Next, APAC argues that the Settlement violates the Bonneville Power Act, 16 U.S.C. § 832d(a), because it does not permit BPA to cancel any contract with five years’ notice. The Bonneville Power Act provides the following cancellation requirements for contracts:
[I]n the case of a contract with any purchaser engaged in the business of selling electric energy to the general public, the contract shall provide that the administrator may cancel such contract upon five years’ notice in writing if in the judgment of the administrator any part of the electric energy purchased under such contract is likely to be needed, to satisfy the requirements of the said public bodies or cooperatives referred to in this chapter, and that such cancelation [sic] may be with respect to all or any part of the electric energy so purchased under said contract to the end that the preferential rights and priorities accorded public bodies and cooperatives under this chapter shall at all times be preserved.
16 U.S.C. § 832d(a) (emphasis added). We conclude that APAC’s argument fails because such cancellation can occur only if “any part of the electric energy purchased under [the] contract is likely to be needed.” But the Settlement does not deny the COUs’ access to power, because the Settlement guarantees only REP benefits, not actual power, for the IOUs. See generally Util. Reform Project, 869 F.2d at 443-44 (concluding that a particular power exchange between BPA and certain IOUs was “properly viewed as an exchange, rather than a sale, of power,” such that the five-year cancellation clause did not apply, because “BPA’s right to obtain exchange energy” meant there would be “no net diminution to the federal system” and BPA would “therefore continue to have the ability to meet its preference customers’ needs”). Thus, there is no possibility that, under the terms of the Settlement, BPA will be required to provide power to the IOUs, much less power that is needed elsewhere.
E. Compliance with PGE and Golden Northwest
In addition to challenging the Settlement terms that provide benefits to the IOUs, APAC also raises a challenge to the terms that provide refunds to the COUs. *967APAC argues that the Settlement “fails to fulfill the mandate” of PGE and Golden Northwest because it “neither calculates the past overcharges nor provides for refunds with interest.”44 We find no merit to this argument. First, the Settlement addresses the overcharges by providing refunds for the COUs, in an amount totaling $612 million over eight years. As the Administrator explained, this amount “reflects BPA’s calculation of the outstanding Lookback Amount payments ($511 million), adjusted for interest earned over eights years.” ROD 253.45 Second, the very nature of a settlement is that the parties forego certain benefits or rights to which they may have a cognizable legal claim, in exchange for something else— here, guaranteed refunds, future certainty, and the end to ongoing litigation. Short of arguing that the parties to the Settlement have no right to settle, APAC cannot plausibly claim that the Settlement is invalid because it does not provide for the full amount of refunds to which the COUs may have been entitled, absent the Settlement. “An agency’s discretion is at its zenith when it is fashioning policies, remedies and sanctions.... ” Pub. Utils. Comm’n of State of Cal. v. F.E.R.C., 462 F.3d 1027, 1053 (9th Cir.2006) (emphasis added) (internal quotation marks and alteration omitted). We therefore will not disturb the Settlement’s refund schedule for the COUs, which all settling parties agreed to and which the BPA Administrator approved.
F. Enforcement of Settlement on Non-Binding Parties
APAC next argues that the Settlement is only a “partial settlement,” which “does not resolve all claims between all adverse parties” and cannot bind the non-signatories. This is true: the Settlement cannot, and does not, bind any parties that have not signed it. But this does not mean that BPA is prohibited from setting the same rates for signing and non-signing parties. As BPA argues, it has the statutory authority to set rates and to recover costs through those rates, pursuant to section 7 of the NWPA. See 16 U.S.C. § 839e. So long as the Settlement complies with the relevant statutory authority — as we have concluded that it does — BPA does not need its customers to unanimously agree to the rates it sets in accordance with the Settlement. We agree with the Administrator’s explanation of the Settlement:
Non-signers are bound only in the sense that they will pay in rates the REP benefits provided under the Settlement, but only after BPA has independently found that the Settlement satisfies the requirements and protections set forth in the [NWPA], This is not the same thing, though, as treating non-signers as if they have executed the Settlement. For example, pursuant to section 7.10 of the Settlement, signers may not “directly or indirectly challenge, either in whole or in part, the legality of the Settlement Agreement or any REP Settlement Implementation Agreement.” Non-signers are not so limited.
*968ROD 348.46 In other words, our conclusion that BPA can lawfully set the same rates for signing and non-signing parties does not necessarily preclude non-signing parties from challenging those rates going forward. Cf. ROD 325 (“[A]s a legal matter, BPA’s decision to execute the Settlement (and therefore become a ‘Party’), and BPA’s decision to replace its previous disputed decisions with the Settlement and this ROD, may have an effect on [parties’] pending claims.”). We therefore conclude that the Settlement does not improperly bind non-settling parties to the Settlement.
G. Fairness and Reasonableness of the Settlement
Finally, APAC argues that the Settlement is neither fair nor reasonable, and that the Administrator’s conclusion to the contrary is “arbitrary and capricious.” See 5 U.S.C. § 706(2) (providing that a court shall “hold unlawful and set aside agency actions, findings, and conclusions” that are “arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law”). APAC essentially re-caps the same arguments we have rejected supra, arguing, inter alia, that the COUs have “forfeited” the protections of the section 7(b)(2) rate test, that several of the tested scenarios did not result in lower REP benefits under the Settlement than would be distributed without the Settlement, that the Settlement improperly projects costs over a seventeen year period, that the Settlement improperly waives BPA’s in-lieu power and prevents it from allocating CRAC costs to the IOUs, and that the Settlement’s value to the COUs is “overstated,” since the COUs are entitled to greater refunds pursuant to PGE and Golden Northwest. We reject these arguments for the reasons provided supra. The Settlement is lawful. Furthermore, the BPA Administrator engaged in an exhaustive evaluation of the Settlement, providing thorough analyses and conclusions for countless challenges raised during the administrative proceedings. We therefore conclude that the BPA Administrator’s adoption of the REP-12 Settlement in the REP12 Record of Decision was not arbitrary or capricious.
IV. CONCLUSION
For the foregoing reasons, APAC’s petition for review is DENIED.
. At the time of the BPA Administrator’s final decision in this case, there were 56 petitions pending before the Ninth Circuit "on issues related to BPA’s establishment of its power rates.’’ Record of Decision 13.
. The REP-12 Record of Decision is contained in BPA's supplemental excerpts of record, filed with the court. It is also available at http://www.bpa.gov/Finance/Residential ExchangeProgram/Pages/default.aspx. We cite to the page numbers of the Record of Decision, rather than to the parties' supplemental excerpts of record.
.APAC's petition was initially consolidated with Alcoa Inc. v. BPA, No. 11-73161. However, BPA and Alcoa later reached a settlement of their dispute and agreed to dismiss that action under Rule 42(b) of the Federal *944Rules of Appellate Procedure. We dismissed Alcoa's petition with prejudice on December 18, 2012.
. The intervening parties are: a group of investor-owned utilities ("IOUs”), a group of consumer-owned utilities ("COUs”), and the Citizens' Utility Board of Oregon. All intervening parties urge the court to dismiss or deny APAC’s petition.
. "BPA's authority to market power is derived from four separate acts: the Bonneville Project Act; the Regional Preference Act of 1964, 16 U.S.C. §§ 837-837k (2000); the Federal Columbia River Transmission System Act, 16 U.S.C. §§ 838-838k (2000); and the [NWPA], 16 U.S.C. §§ 839-839h (2000).” PGE, 501 F.3d at 1014 n. 2. BPA "originally operated under an annual congressional appropriation, but was restructured as a self-financed agency in 1974.” Id. at 1014.
. Section 5(c) technically makes REP benefits available to any qualified utility, including COUs. See 16 U.S.C. § 839c(c)(1). But it was intended primarily to benefit the IOUs, and the Settlement guarantees REP benefits only to IOUs. See Washington Utilities & Transp. Comm’n (WUTC) v. F.E.R.C., 26 F.3d 935, 936-37 (9th Cir.1994) (“The exchange program is designed to eliminate the disparities between electric rates paid by residential customers of IOUs and the lower rates paid by customers of publicly-owned utilities”). For these reasons, and for the sake of clarity, we refer to “IOUs,” rather than “utilities,” as the relevant beneficiaries of section 5(c).
. BPA determines an IOU’s ASC “on the basis of methodology developed for this purpose in consultation with the [Pacific Northwest Electric Power and Conservation Planning] Coun*946cil, the Administrator’s customers, and appropriate State regulatory bodies in the region.” 16 U.S.C. § 839c(c)(7). The ASC methodology is subject to review and approval by the Federal Energy Regulatory Commission (“FERC”). BPA's current methodology was developed in 2008 and approved by FERC in 2009. ROD 3.
. The rate that BPA charges its preference customers is the "Priority Firm Public rate,” or "PF Public rate.” See ROD xi, 180, 185, 330; see also 16 U.S.C. §§ 839c(b), 839e(b); Pac. Nw. Generating Co-op., 580 F.3d at 802. This rate is also referred to as the "PF Preference rate.” ROD 7; see also ROD 203.
.We explained that BPA had erroneously relied on a "set of assumptions ... [that] served to enlarge the group of IOUs eligible for the settlement and to increase the benefits of those already qualified for the REP,” including (1) the possibility of a legal challenge to the methodology for rate-making, despite the lack of any such existing challenge, (2) the possibility of a challenge to the PF Exchange rate, and (3) future fluctuations in the energy market. PGE, 501 F.3d at 1033.
. The BPA Administrator publicly urged customers to work toward a settlement that would "provide greater long-term certainty” and "greater political equity” than what BPA could provide on its own. ROD xvii.
. The settling parties consist of all six regional IOUs, three public utility commissions, several customer representative groups, the Citizens' Utility Board of Oregon,’ and 89.1 percent (by load) of the COUs.
. The lump sum allocated to the IOUs reflects the resolution of all disputed claims arising from fiscal years 2002-2011, as well as the IOUs’ entitlement to REP benefits for fiscal years 2012-2028. Id.
. The Settlement sets forth a specific formula for determining whether an individual IOU qualifies for REP benefits, and if so, what amount of REP benefits it should receive. See ROD Appendix A 19-20. We discuss this formula infra, in Part III.A.l.b.
. The three scenarios in which the COUs' rates were higher under the Settlement were scenarios that presumed the COUs would prevail on all their major contested legal issues and the IOUs would prevail on none; BPA deemed this unlikely. ROD 80-81.
. These refunds are referred to by the parties as "Lookback Amounts,” and are the subject of numerous pending petitions before this court. See ROD 13-15.
. These groups are Georgia-Pacific LLC, Grays Harbor Paper LP, JR Simplot Co., Longview Fibre Paper and Packaging, Inc., Ponderay Newsprint Company, and Weyerhaeuser Company.
. APAC filed this affidavit with our court in order to establish standing. "Because Article Ill’s standing requirement does not apply to agency proceedings, petitioners had no reason to include facts sufficient to establish standing as a part of the administrative record. We therefore consider the affidavit!] not in order to supplement the administrative record on the merits, but rather to determine whether petitioners can satisfy a prerequisite to this court’s jurisdiction.” Nw. Envtl. Def. Ctr. v. Bonneville Power Admin., 117 F.3d 1520, 1527-28 (9th Cir.1997).
APAC also submitted an affidavit from the general manager of a group called “Grays Harbor PUD.” This affidavit addresses the former contractual relationship between “Grays Harbor Paper Company” and a COU, but suggests that Grays Harbor Paper Company no longer exists. It also fails to state whether Grays Harbor Paper Company is or was a member of APAC. Because we can resolve the question of standing on the basis of the affidavit from Georgia-Pacific LLP, we do not rely on the affidavit from Grays Harbor PUD.
.In its description of GP’s contractual relationship with CLPUD, the affidavit replaces "CPUD” with "CLPUD,” deletes the phrase "and other sources,” and replaces "Wauna mill” with "Toledo plant.”
.We consider the standing of APAC’s individual members because an organization has standing to sue on behalf of its members if " '(a) its members would otherwise have standing to sue in their own right; (b) the interests it seeks to vindicate are germane to the organization's purpose; and (c) neither the claim asserted nor the relief requested requires the participation of individual members in the lawsuit.’ ” Smith v. Pac. Properties & Dev. Corp., 358 F.3d 1097, 1101-02 (9th Cir.2004) (quoting Hunt v. Wash. State Apple Advert. Comm’n, 432 U.S. 333, 343, 97 S.Ct. 2434, 53 L.Ed.2d 383 (1977)); see also Ocean Advocates v. U.S. Army Corps of Engineers, 402 F.3d 846, 859-61 (9th Cir.2005) (concluding that organization had standing because one of its members had standing). BPA and the intervenors do not contend — nor do we have any reason to believe — that the latter two requirements are not satisfied.
. APAC also argues that the Settlement fails to reimburse the COUs for illegal overcharges resulting from the 2000 REP Settlement Agreement, which we struck down in PGE and Golden Northwest.
. BPA does not dispute that APAC’s members may suffer an injury in fact; it instead focuses on the second and third requirements for constitutional standing, arguing that "any burden imposed on APAC’s members comes from the COUs that sell power to them,” and any remedy must also come from the COUs. See infra, at Part III.A. 1 .b-c.
. The intervening IOUs confuse two separate inquiries: (1) the Article III "legally protected interest” inquiry, which is a part of establishing "injury-in-fact,” and (2) the prudential standing inquiry, which looks to whether a relevant statute confers a right to sue upon a *951particular plaintiff. But it is only after determining that "a plaintiff has suffered sufficient injury to satisfy Article III” that the court "ask[s] whether a statute has conferred 'standing' on that plaintiff” as part of the prudential standing inquiry. Cetacean Cmty., 386 F.3d at 1175 (emphasis added); see also Salmon Spawning & Recovery Alliance v. Gutierrez, 545 F.3d 1220, 1224-25 (9th Cir.2008).
. The exact requirements for a "legally protected interest” are far from clear. See, e.g., In re Special Grand Jury 89-2, 450 F.3d 1159, 1172 (10th Cir.2006) (explaining that the term has “generated some confusion,” but concluding that the interest need not be "protected by law ... so long as it is the sort of interest that courts think to be of sufficient moment to justify judicial intervention”); Judicial Watch, Inc. v. U.S. Senate, 432 F.3d 359, 363 (D.C.Cir.2005) (Williams, Senior J., concurring) (expressing “puzzlement” over the requirement and discussing the "powerful reasons" it should be interpreted to "simply reformulate[ ] pre-existing requirements, particularly that the interest affected be a cognizable one”).
. The dissent misconstrues our explanation here that a legally protected interest need not be a statutorily created interest as a suggestion that it is "inappropriate to examine the statute in the context of a legally cognizable interest.” See Dissent at 972-73, n. 9. We make no such suggestion. Our point is only that a legally protected interest can derive from a source other than a statute.
.The dissent asserts that Central Arizona is distinguishable because in that case EPA was acting in its regulatory capacity while in this case BPA acted "within its power to contract [with the COUs] by adopting the REP 12 Settlement Agreement.” Dissent at 975. This distinction makes no difference. Central Arizona is analogous because, just as the pecuniary impact of EPA’s regulations passed through to the purchasers of power from the generating system, the pecuniary impact of BPA’s actions passed through to GP. The pass-through contracts that GP has with the two COUs discussed in GP’s affidavit forms the basis for APAC's Article III standing. BPA's own authority to enter into a contractual relationship with the COUs does not somehow render GP a mere downstream customer without standing, as the dissent argues. Nor does it mean that GP seeks to establish standing by asserting the rights of a third party. See Dissent at 975-76. There is a direct cor*952relation between the REP-12 Settlement and the costs that GP will shoulder. The alleged injury is GP’s own, not that of the COUs or any other third party.
. The dissent devotes an extensive part of its discussion to confronting arguments on which we do not rely to hold that APAC has standing. For instance, we do not hold that APAC has standing because its members are "significant purchasers” of BPA power. See Dissent at 974. Nor do we hold that all downstream consumers of energy, including residential customers, have standing to challenge the Settlement or any other action by BPA. See Dissent at 973-74. Our holding is limited to the unique facts of this case. Further, because APAC filed an affidavit on behalf of GP, which is uncontested, we do not need to address the "burden of production” issue raised by the dissent. See Dissent at 971, n. 7.
. APAC argues that BPA has waived any challenge to APAC's prudential standing by failing to raise it during the REP-12 proceedings before the agency. Unlike Article III standing, the issue of a party's prudential standing can be waived if not raised in a timely manner. See Pershing Park Villas Homeowners Ass'n v. United Pac. Ins. Co., 219 F.3d 895, 899 (9th Cir.2000). But here, BPA had no reason to challenge APAC's prudential standing before filing its answering brief, since REP proceedings are not subject to standing requirements. See Overton Power Dist. No. 5 v. O’Leary, 73 F.3d 253, 257 (9th Cir.1996) ("[I]t does not necessarily follow that a party able to participate in administrative proceedings therefore has standing to challenge agency decisions.”); see also 16 U.S.C. § 839(3)(B) (stating that one of the purposes of the NWPA is "to provide for the participation and consultation of the Pacific Northwest States, local governments, consumers, customers, users of the Columbia River System ... and the public at large within the region” in “facilitating the orderly planning of the region's power system”). Thus, BPA has not waived this challenge.
. The "zone of interest'' requirement derives from section 10 of the APA, which provides that "[a] person suffering legal wrong because of agency action, or adversely affected or aggrieved by agency action within the meaning of a relevant statute, is entitled to judicial review thereof.” 5 U.S.C. § 702. The Supreme Court has "interpreted § 10(a) of the APA to impose a prudential standing requirement in addition to the requirement, imposed by Article III of the Constitution, that a plaintiff have suffered a sufficient injury in fact.” Nat’l Credit Union Admin., 522 U.S. at 488, 118 S.Ct. 927.
. In addition to arguing that the Settlement is unlawful because it violates the NWPA, APAC also argues that the Settlement is unlawful because it violates the Bonneville Power Act and related FERC regulations. However, this argument is wrapped into APAC's argument that the Settlement violates the NWPA, insofar as the NWPA incorporates the relevant provisions of Bonneville Project Act. 16 U.S.C. § 839c(a) (stating that all power sales conducted pursuant to section 5 of the NWPA are “subject at all times to the preference and priority provisions of the Bonneville Project Act of 1937 (16 U.S.C. § 832 and following) and, in particular, sections 4 and 5 thereof [16 U.S.C. §§ 832c, 832d]''). We therefore need not separately consider whether APAC's interests line up with the statutory purposes of the Bonneville Power Act.
. Put in more mathematical terms, APAC argues that the value of the "REP Benefit” must be the dependent variable in the formula derived from section 5(c).
. This, of course, raises the "critical question” of "whether the aggregate REP benefits provided under the Settlement exceed what the [NWPA] permits.” ROD 116. We address that question infra in Part III.B.
.We also reject APAC’s argument that reference to "a Pacific Northwest electric utility,” 16 U.S.C. § 839c(c)(l) (emphasis added), is *958evidence of "Congress’ intent to provide benefits only on an IOU-specific basis.” First, section 5(c)(1) is silent with respect to "calculating the exchange benefits for the IOUs as a class.” ROD 92. We therefore defer to the Administrator’s reasonable interpretation of section 5(c)(1), which allows BPA to settle its REP obligations. Id.; see also ROD 98 (explaining that under APAC’s interpretation of section 5(c), "BPA has no choice but to implement the traditional REP,” and in that case "there could be no settlement of the REP”); PGE, 501 F.3d at 1037 ("BPA has broad authority to settle claims under the NWPA.”). Second, even under the Administrator’s interpretation of section 5(c), BPA still must provide benefits on an IOU-specific basis, for the reasons discussed in this section.
. I Put another way, if we start from two premises — first, that the total amount of aggregate REP benefits is lawful, and second, that the REP benefits are distributed proportionately among all IOUs — we must necessarily conclude that the total amount of REP benefits distributed to any particular IOU is lawful.
. The formula is best understood when broken into sub-parts. First, BPA will calculate the difference between an individual IOU’s ASC and the base rate for power in that fiscal year, and multiply that amount by the IOU's power load:
(ASC - Base Rate) x (Load) = A
The value of "A” will be different for each IOU, since it is dependent on that IOU’s particular ASC and load.
Second, BPA will divide the total amount of REP settlement benefits in a given year — that is, the lump sum provided for all IOUs in that year — by the total sum of all of the "A” values, as calculated for each IOU using the formula above:
(Total REP Settlement Benefits) = B
2((ASC — Base Rate) x Load))
This creates a scaled value that will be the same for all IOUs, since it does not rely on any IOU-specific values.
Third, BPA will multiply A times B:
([ (ASC — Base Rate) x (Load) ] x [ (Total REP Settlement Benefits)/(2 ((ASC - Base Rate) x Load)) ]) = C
This third step serves to divide the aggregate REP benefits among the IOUs in a way that is *959proportional to their ASCs: a higher ASC results in a greater difference between the ASC and the base rate, which results in a greater value for "A,” which in turns results in a greater value for "C."
Finally, BPA will add the amount of any "6.2 adjustment,” resulting in the final REP Benefit for that IOU:
C + [Section 6.2 adjustment] = REP Benefit
This final step involves a “reallocation” of REP benefits among the IOUs, which reflects the fact that the IOUs have not received equal refund payments from BPA thus far. ROD 120. Thus, "some [IOUs] have agreed to take a larger amount of rate protection in the calculation of their PF Exchange rate, while others have agreed to take less.” ROD 121. This internal reallocation of benefits among the IOUs does not affect any other class of BPA ratepayers. See id. (concluding that "[n]othing in section 5(c), section 7(b)(2), or section 7(b)(3) prohibits the IOUs from waiving their rights to have rate protection dollars allocated on a pro rata basis among the PF Exchange rates”).
. Consider, for example, a scenario where an IOU’s ASC is 40.00, the' base rate for power is 30.00, and the PF Exchange rate is 50.00. Under the formula used in the Settlement, the IOU would qualify for some portion of the REP benefits. Under the formula traditionally used, however the IOU would not qualify for any REP benefits, because 40 — 50 = 10.
. See discussion infra Part III.B.
. This would occur if one or more of the IOUs did not qualify for REP benefits under the formula set forth in the Settlement.
. We further note that BPA staff “worked with the parties to test the formulas in the Settlement to ensure they would function over time,” which included identifying a potential "anomalous scenario” that could occur if “BPA’s cost of power was higher than all of the IOUs’ cost of power.” ROD 116-17.
.The in-lieu provision of section 5 provides: "Subject to the provisions of sections 839b and 839d of this title, in lieu of purchasing any amount of electric power offered by a utility under paragraph (1) of this subsection, the Administrator may acquire an equivalent amount of electric power from other sources to replace power sold to such utility as part of an exchange sale if the cost of such acquisition is less than the cost of purchasing the electric power offered by such utility.” 16 U.S.C. § 839c(c)(5).
. In practice, however, BPA has never actually exercised this power. ROD 132; see also Cal. Energy, 807 F.2d at 1461 (explaining that in-lieu purchases are “but a minor feature of the exchange program created in section 5,” with "only'a very limited usefulness’’).
. Furthermore, as the BPA Administrator explained, the argument that "the duration of the 2012 Settlement ... is unprecedented” not only fails to show that the Settlement is unlawful, it is also "simply wrong.... During the 1980s and 1990s, BPA negotiated REP settlement agreements and paid benefits under such agreements to 33 exchanging utilities, including all of BPA's exchanging preference customers, for terms up to 15 years.” ROD 201.
. These twenty-six scenarios consisted of "four scenarios to analyze uncertainty in BPA’s costs and [twenty-two] scenarios to analyze the possible impact of the litigation outcomes.” ROD 56-58. As the Administrator noted, "the lower projected costs of the REP ... are not mere ethereal guesswork.” ROD *96460. In making these projections, BPA considered "multiple variations on the key drivers of future REP benefits, i.e., ASCs, exchange loads, BPA's costs, litigation risks, and market variations.” ROD 64. Thus, although the very nature of forecasting implies some uncertainty, the rates that BPA forecast cannot fairly be characterized as, in APAC’s words, "pure speculation and conjecture.”
. All power sales conducted pursuant to section 5 of the NWPA are “subject at all times to the preference and priority provisions of the Bonneville Project Act of 1937 (16 U.S.C. 832 and following) and, in particular, sections 4 and 5 thereof [16 U.S.C. §§ 832c, 832d]." 16 U.S.C. § 839c(a).
. APAC also argues that the Settlement does not comply with PGE and Golden Northwest. because it violates section 5 and section 7 of the NWPA. We reject this argument for the reasons explained in our analysis of those provisions, supra.
. After our decisions in PGE and Golden Northwest, but before the Administrator approved the Settlement, BPA provided partial refunds to the COUs for over-charges under the 2000 Settlement. Adding these refunds to the $612 million guaranteed under the Settlement, "the total refund payments BPA will have made to the COUs will be approximately $1.2 billion.” ROD 253.
. See also ROD 322 ("In terms of whether the Settlement provides equity to non-settling parties, BPA believes the non-settling parties are being treated equitably under the Settlement because they will benefit from the return of the Refund Amounts and resolution of the past refund payments."); ROD 361 ("The conclusion is that under most possible future results of the rate test, rates for COUs would be higher than the rates under the Settlement. ... Thus, BPA is not imposing rates on non-signing customers that would deny such customers their statutory 7(b)(2) protection.”); ROD 372 ("Because the Settlement is consistent with BPA's rate-setting directives, file statutory protections of non-settling entities are not being violated by the Settlement.”).
. APAC is the only party challenging the REP-12 Settlement Agreement. APAC's petition initially was consolidated with Alcoa Inc. v. Bonneville Power Administration, No. 11-73161. BPA and Alcoa later settled their dispute and agreed to dismiss that action under Rule 42(b) of the Federal Rules of Appellate Procedure. This Court dismissed Alcoa's petition with prejudice on December 18, 2012.