Task: songer_usc1

What follows is an opinion from a United States Court of Appeals.
Your task is to identify the most frequently cited title of the U.S. Code in the headnotes to this case. Answer "0" if no U.S. Code titles are cited. If one or more provisions are cited, code the number of the most frequently cited title.

Opinion
PER CURIAM.
Concurring Opinion filed by Circuit Judge MacKINNON.
TABLE OP CONTENTS
Page
Introduction........................ 575
I. Background.................... 575
A. Legislative requirements...... 575
B. Prior ratemaking proceedings.. 577
II. Nos. 75-1856, 75-1857: The NAGCP
case........................... 577
A. 39 U.S.C. § 3601............. 578
B. 39 U.S.C. § 3622............. 580
1. Commission’s approach to section 3622 (b)(3) and ALJ’s alternative approach...... 581
a. Attribution.......... 581
b. Assignment.......... 582
c. Alternative approaches.. 583
2. Requirements of section 3622 584
a. Interpreting subsection
3622(b)(3)............ 585
b. Compliance with the Act 590
(1) Attribution........ 590
(2) Assignment........ 592
III. Nos. 75-2227, 75-2228 and No. 75-2238: The ATCMU and the State of Maine cases.................. 593
A. The ATCMU case............ 594
1. Proposed changes in fees for
special services........... 595
2. Request for changes in postal
rates and fees............ 598
B. The State of Maine case....... 602
PER CURIAM:
These three cases, consolidated for consideration on the merits, raise a full range of substantive and procedural challenges to a series of orders of the United States Postal Service (“Postal Service” or “USPS”) issued pursuant to the Postal Reorganization Act of 1970 (“Act”), 39 U.S.C. § 101 et seq., for the purpose of implementing certain increases in postal rates and fees, either temporarily or on a permanent basis. In Nos. 75-1856, 75-1857 — the National Association of Greeting Card Publishers (“NAGCP”) case — we review the permanent rates that were in effect from September to December, 1975. In Nos. 75-2227, 75-2228 and No. 75-2238 — the Associated Third Class Mail Users (“ATCMU”) and State of Maine cases, respectively — we review the temporary rates that were in effect from December, 1975 to July 18, 1976. Viewed together these cases prompt us not only to decide the individual merits of each claim but also to consider the Postal Service’s overall progress to date in adapting to the Act’s special, and quite demanding, ratemaking requirements. We bring to this task our prior experience in interpreting the complex procedures by which postal rates and fees are set under the Act.
I. BACKGROUND
While each case before us offers its own unique theory for invalidating the rates or fees it challenges, all three cases require an understanding of the ratemaking procedure prescribed in the Act.
A. Legislative Requirements
Briefly put the Act created the Postal Service, “an independent establishment of the executive branch of the Government of the United States,” which is directed by an eleven member Board of Governors (“Board”) composed as follows: nine presi-dentially appointed “Governors”; the Postmaster General, who is the “chief executive officer of the Postal Service” and is appointed by the Governors; and the Deputy Postmaster General, who is appointed by the Governors and the Postmaster General. Some powers are conferred on the Governors as distinct from the Board. The Act also created the independent, five member Postal Rate Commission (“Commission”) which is charged with submitting to the Governors, upon request, “recommended decision[s] on changes in a rate or rates of postage or in a fee or fees for postal services.”
The ratemaking procedure prescribed by the Act may be summarized as follows. The Postal Service submits to the Commission a formal request for new rates or fees, which request may be accompanied by suggestions for rate adjustments which the Postal Service deems suitable. The Commission must provide an opportunity for a hearing on the record and, at the conclusion of this proceeding, must transmit its recommended decision to the Governors. The Governors then may approve the decision and order it into effect, or allow it to take effect under protest while seeking judicial review or Commission reconsideration, or reject it and have the Postal Service resubmit the request for reconsideration and a further recommended decision in which event the further recommended decision may, under limited circumstances, be modified by the Governors and put into effect as modified. An aggrieved party who appeared in the Commission proceedings may appeal the “decision of the Governors to approve, allow under protest, or modify the recommended decision,” and the reviewing court “may affirm the decision or order that the entire matter be returned for further consideration, but the court may not modify the decision.”
To avoid any prolonged disruption to the Postal Service’s financial integrity which compliance with this elaborate procedure might cause, the Act also provides for the implementation of temporary increases in rates or fees. If the Commission “does not transmit to the Governors within 90 days after the Postal Service has submitted, or within 30 days after the Postal Service has resubmitted, to the Commission a request for a recommended decision... the Postal Service, upon 10 days’ notice in the Federal Register, may place into effect temporary changes in rates of postage [or] in fees for postal service.” A temporary rate or fee, however,
may not exceed the lesser of (1) the rate or fee requested for such class or service, or (2) a rate or fee which is more than one-third greater than the permanent rate or fee in effect for that class or service at the time a permanent change in the rate or fee of such class or service is requested under section 3622 of this title.
In addition, if upon judicial review of a decision of the Governors on permanent rates, taken pursuant to 39 U.S.C. § 3628, the court “orders a matter returned to the Commission for further consideration, the Postal Service, with the consent of the Commission, may place into effect temporary [rates or fees].” Finally, judicial review of temporary rates or fees may be sought in the district court.
B. Prior Ratemaking Proceedings
To date three ratemaking proceedings have been initiated under the Act. The first proceeding (docket no. R71-1), which may be identified by its establishment of permanent 8 cent first class rates, began when the Postal Service submitted a request on February 1, 1971. Temporary rates were put into effect May 16,1971, and on June 29, 1972, the Governors approved the Commission’s recommended decision and ordered permanent rates put into effect. On appeal pursuant to 39 U.S.C. § 3628 this Court affirmed the Governor’s order. Association of American Publishers, Inc. v. Governors of the United States Postal Service, 157 U.S.App.D.C. 397, 485 F.2d 768 (1973) [hereafter cited as American Publishers ].
The second proceeding (docket no. R74-1) established 10 cent first class rates. It was initiated with a request on September 25, 1973; temporary rates were put into effect March 2, 1974; and permanent rates were ordered September 4,1975, after nearly two years of Commission proceedings. The NAGCP case seeks judicial review of this order pursuant to 39 U.S.C. § 3628.
The latest proceeding (docket no. R76-1), which may be identified by its proposal to establish permanent 13 cent first class rates, began with a request that was submitted September 18, 1975, and was resubmitted December 19, 1975. The ATCMU and State of Maine cases were brought in district court to enjoin implementation of temporary rates based on this request. Following district court orders in which injunc-tive relief was granted on procedural grounds (ATCMU), but denied on substantive grounds (State of Maine), appeals were taken to this Court. We stayed the district court injunction, and on December 31, 1975, temporary 13 cent first class rates were put into effect.
II. Nos. 75-1856, 75-1857: THE NAGCP CASE
The first case involves the second rate-making proceeding conducted under the Act and is before us on NAGCP’s petition to review the September 4, 1975 order of the Governors which approved the Commission’s recommended decision and ordered into effect the permanent rates there recommended.
In that proceeding the Commission, after receiving the Postal Service’s September 25, 1973 request for a recommended decision, assigned Chief Administrative Law Judge (“ALJ” or “Judge”) Seymour Wenner, who had presided at the first ratemaking proceeding, to preside at the hearing. Taking part in the hearing, which began June 27,1974, were some 29 full participants and 17 limited participants. Extensive evidence was taken over some 46 days of hearings, the record being closed on December 20, 1974.
After briefing, issuance of the ALJ’s initial decision (May 28,1975), and two days of oral argument before the Commission, the case was submitted to the Commission, which transmitted its recommended decision to the Governors on August 28, 1975. The Governors’ implementing order and this appeal followed.
A. 39 U.S.C. § 3601
At the. outset we are met with the contention that the Commission, at the time it considered and composed its recommended decision, was improperly constituted under the Act and that therefore the actions it took, regardless of their validity otherwise, are without force and effect.
Section 3601 of the Act establishes the Commission and mandates that it be “composed of 5 Commissioners appointed by the President, not more than 3 of whom may be adherents of the same political party.” At the time in question three of the Commissioners were members of the Republican Party while one was a member of the Conservative Party of New York State. The claim of improper composition rests in essence on the assertion that these two political parties are “the same political party” within the meaning of section 3601.
No claim is made that the organization of either party is a sham or that one party exercises control over the other. Rather, the heart of the argument is an assertion of sameness predicated on an evaluation of certain similarities in the political philosophies of the two parties. Believing it well outside our proper judicial role to undertake such an analysis, we exercise no jurisdiction and express no views whatsoever on the issue. See Baker v. Carr, 369 U.S. 186, 217, 82 S.Ct. 691, 7 L.Ed.2d 663 (1962); Coleman v. Miller, 307 U.S. 433, 453-54, 59 S.Ct. 972, 83 L.Ed. 1385 (1939).
Furthermore, even were we to assume that the Commission was improperly composed, there is a separate and independent reason why the actions here challenged would still be valid. At least since Ex parte Ward, 173 U.S. 452, 19 S.Ct. 459, 43 L.Ed. 765 (1899), the law has been clear that;
A person actually performing the duties of an office under color of title is an officer de facto, and his acts as such officer are valid so far as the public or third parties who have an interest in them are concerned.
United States ex rel. Doss v. Lindsley, 148 F.2d 22, 23 (7th Cir. 1945), cert. denied, 324 U.S. 863, 65 S.Ct. 866, 89 L.Ed. 1419 (1945); see United States v. Krueger, 319 F.Supp. 225, 226-27 (N.D.ILL.1970). In short, the remedy for improper composition is not invalidation of the Commission’s action through indirect challenge, but rather removal of the allegedly disqualified Commissioner by way of direct attack. See, e. g., Ryan v. Hershey, 445 F.2d 560 (8th Cir. 1971), cert. denied, 404 U.S. 1004, 92 S.Ct. 565, 30 L.Ed.2d 557 (1971); United States v. Chaudron, 425 F.2d 605 (8th Cir. 1970), cert. denied, 400 U.S. 852, 91 S.Ct. 93, 27 L.Ed.2d 89 (1970); United States v. Brooks, 415 F.2d 502 (6th Cir. 1969), cert. denied, 397 U.S. 969, 90 S.Ct. 1003, 25 L.Ed.2d 263 (1969). B. 39 U.S.C. § 3622
On the merits the case focuses on 39 U.S.C. § 3622, the section of the Act which sets forth the cost and noncost considerations that the Commission must take into account in setting rates. The “most concrete” of these, and only one of the subsections which deals expressly and exclusively with cost factors, is subsection 3622(b)(3) which establishes
the requirement that each class of mail or type of mail service bear the direct and indirect postal costs attributable to that class or type plus that portion of all other costs of the Postal Service reasonably assignable to such class or type.
In response to section 3622 the Commission developed for this proceeding, and the Governors adopted by their order, a two-step process for allocating among the classes of mail all the costs of operation. While each step will be described more fully below, the Commission’s approach may be summarized at the outset as follows. The Commission sought as its first step to identify and allocate to each class of mail those costs which in its view indisputably were the result of providing that particular service. A rate floor for each class of mail, see note 58 and accompanying text infra, was thus established by “attributing” a portion of the total costs on the basis of “cost variability” — an approach which evaluates changes in costs as a function of changes in output volume. As its second step, in order to take into account the noncost factors of section 3622, the Commission then judgmentally “assigned” all the remaining costs on the basis of demand factors designed to determine “what the traffic will bear” in each class of mail. Under this “inverse elasticity rule” approach, final rates evolved by assigning all the unattributed costs to the various classes of mail in inverse proportion to the relative elasticity of demand for each class; i. e., those classes of mail in which increases in rates hypothetically would cause lesser decreases in patronage were made to shoulder larger portions of the unattributed costs, while those with greater elasticity of demand were burdened with smaller markups above their attributed costs. Petitioner advances separate arguments to dispute each element of the Commission’s approach.
1. Commission’s Approach to Subsection 3622(b)(3) and ALJ’s Alternative Approach.
a. Attribution. The premise of the Commission’s approach to attribution is its belief that cost variability is the only proper indicator of causation. As the Commission explains,
if a particular cost varies with a change in volume units, we infer that the cost is caused by such change and can be attributed to the class or service experiencing the change.
From volume variability, therefore, we can infer, and thereby establish, the causation that we seek. And by establishing minimum rates based on variable costs, we assure ourselves, the public, and Congress that no class has cross-subsidized any other class.
The basic principles of this cost-of-service approach have remained unchanged since the Commission first adopted cost variability as its attribution methodology in the initial rate proceeding.
The touchstone of the cost variability approach is the Commission’s concern that causation be measured as accurately as possible — that within the bounds of available data, all elements of approximation or estimation be excluded.
[W]e believe that causation is both the statutory and the logical basis for attribution. Where an analysis based on causation cannot be made because data are lacking, we will do better to acknowledge that fact and press for a better data base than to construct an “attribution” on a basis not contemplated by the statute.
The stricture of this approach and the unavailability of complete data led in the first two rate proceedings to recommended decisions which, by the Commission’s own account, did not attribute to each class all the costs that likely were the result of providing the particular service. In the first proceeding attributable costs were set at 49% of total costs. In the proceeding here under review the Commission, after revising upward the Service’s proposal to attribute only 45.1% of costs, recommended that 52.5% of all costs be attributed.
b. Assignment. The Commission used demand theory to assign all the remaining, unattributed costs (47.5%). An understanding of the Commission’s approach requires an initial familiarity with the concept of demand elasticity. Simply put, the demand for a product is said to be elastic if lowering its price by a specific percentage leads to a greater percentage increase in the volume sold, or if raising its price by a specific percentage leads to a greater percentage reduction in its volume.
Elasticity of demand forms the cornerstone of a demand theory (or “value-of-service”) approach to apportioning costs. Such an approach seeks to minimize the impact that an increase in rate will have on services with positive demand elasticities by “impos[ing] on the services in relatively inelastic demand... higher surcharges, over and above marginal costs, than would be imposed by any rule of apportionment based exclusively on cost relationships.”
The Commission has developed, and used in both the first and second rate proceedings, a specific formulation of demand theory — what it calls the “inverse elasticity rule” — as a guide in assigning unattributed costs. Under this rule final rates are derived by assigning to the various classes of mail different markups (above attributed costs) in inverse proportion to the relative elasticity of demand for each of the classes. It is the Commission’s position that generally by using demand factors, and specifically by testing its recommended rates against the inverse elasticity rule, it “can assign costs in a manner that fully takes into account the noncost factors of the statute.”
The Commission acknowledges that all classes of mail are basically insensitive to price increases, and that demand in each class, at least at present and reasonably foreseeable rates, is technically inelastic— that is, a rate increase in any class of mail will necessarily generate an increase in revenue albeit at reduced volume. Generally demand theory is used to minimize the impact that a rate increase otherwise would have on products that are demand elastic. The Commission posits, however, that despite the high degree of inelasticity that presently prevails among all classes of mail, demand theory is nonetheless proper in postal ratemaking since it may be based on relative demand elasticities (or, more accurately, relative inelasticities). Accordingly, in the instant proceeding the Commission purported to develop a ranking of relative price sensitivity among the classes of mail and, based on this ranking, sought to establish the “optimum rate for each mail class and service,” which it defined as “that rate which maximizes the volume of mail while recovering all the related attributable costs and making some contribution to the fixed overhead, so that in the end total costs are recovered.”
c. Alternative approaches. In recommending its attribution/assignment methodology to the Governors, the Commission rejected entirely the initial decision proposed by Administrative Law Judge Wen-ner and instead stood by the approach it first developed in the inaugural rate proceeding. In that proceeding ALJ (then Chief Examiner) Wenner severely criticized both the Commission’s use of cost variability as its approach to attribution as well as the Commission’s reliance on the inverse elasticity rule as a guideline for assigning all the remaining costs. However, constrained in that proceeding by the minimal cost data presented, the unavailability of alternative methodologies, and the “presumptions that surround an initial effort to formulate rates,” the ALJ as well as this Court left undisturbed the Commission’s initial use of cost variability and demand theory.
When presented in the instant proceeding with the same approach, essentially unchanged, ALJ Wenner determined that the presumptions noted earlier no longer prevented full review. Adopting and refining alternative methodologies advanced by various parties to the proceeding, and using only the data provided in the Service’s own submission, the ALJ proposed to the Commission an entirely different approach to attribution/assignment under which the ALJ attributed some 70.6% of costs and assigned the remaining costs primarily in accordance with cost-of-service rather than value-of-service principles.
The ALJ’s attribution method proceeds from a premise quite at odds with that of the Commission. Whereas the linchpin of the cost variability approach is an abiding concern for the greatest possible accuracy in measuring causation, the ALJ’s alternative approach devalues somewhat the interest in utmost accuracy in order to pursue more fully the goal of maximized attribution. Simply put, the alternative approach relies on cost accounting principles to augment the inferences of causation derived through use of the cost variability theory. Additional attribution results from using distribution keys such as weight, volume and number of pieces of mail to apportion among the postal services affected those cost segments which clearly affect more than one service and which, although not measurably variable on presently available data, are reasonably susceptible to such apportionment. The approach is perhaps best understood by using transportation costs as an illustration of the method as applied.
The transportation segment as constructed by the ALJ includes all the costs the Postal Service incurs, both for purchased and self-furnished services, to carry mail from the patron’s collection point to the receiving point, including, in addition to salaries, the costs associated with the servicing, maintenance and depreciation of vehicles. It does not include, however, the actual delivery function, i. e., handing the mail to the patron or putting it in the patron’s box, which comprises a different cost segment. In the instant proceeding total transportation costs were $2.621 billion, of which the Postal Service attributed only $545 million (21%), characterizing the remaining $2.076 billion as fixed costs subject to judgmental distribution. The ALJ, however, by analyzing the transportation function as being governed by considerations of the weight and cubic volume of the mail handled (as contrasted with the actual delivery function which is more a factor of the number of pieces of mail) was able to attribute $2.565 billion (98%), leaving only $56 million subject to discretionary assignment. His reasoning was straightforward:
The cubic volume of mail determines the number and size of the vehicles required which affects the maintenance, fuel and lease costs. The weight of the mail affects the loading and unloading effort and also bears on the needed carrying strength and operational expenses of the vehicle. The cost of drivers varies with vehicle operations.
The cost of the mail carrier’s walking (or driving a vehicle) over his route is governed by weight and space. What he can carry in his pouch and his hands is affected by the weight (35 pounds maximum under Postal Regulations) and the size (in cubic volume) of the load; this determines how often he must return to the relay box or to his car. The weight and cubic volume of mail also affects the size of the vehicle he needs (where he has one).
The ALJ’s method for assigning the remaining costs is also quite opposed to principles underlying the Commission’s adopted approach; it proposes complete rejection of the inverse elasticity rule. Under the alternative approach each class of mail bears that portion of unattributed costs equal to its proportionate share of attributed costs unless individual and specific consideration of the noncost factors contained in section 3622(b) requires deviation from the standard markup.
2. Requirements of Section 3622. Relying in large measure on the criticism leveled in the ALJ’s initial decision, petitioner argues that the Commission’s attribution assignment approach is violative of the Act in several respects. Initially petitioner asserts that the Commission’s cost variability method is a too restrictive approach for attribution which permits the expense incident to one service to be thrown upon the customers using another service, resulting in unlawful cross-subsidization. See, e. g., Northern Pacific Railway Co. v. North Dakota, 236 U.S. 585, 597-98, 35 S.Ct. 429, 59 L.Ed. 735 (1915). Petitioner also attacks the Commission’s reliance on demand theory, and in particular its use of the “inverse elasticity rule,” as a means for assigning all unattributed cost, arguing that this approach preserves historical rate differentials and otherwise unduly and unreasonably discriminates against first class mail. See 39 U.S.C. § 403(c).
The foundation of both arguments is the assertion that the Act imposes a special obligation that allocation in accordance with cost-of-service principles be carried out as far as reasonably possible. In American Publishers we found “a strong indication” that Congress intended to impose just such a special obligation. In that case, however, in view of “the presumptions that surround an initial effort to formulate rates” we found it unnecessary to go beyond a mere preliminary assessment of the import of subsection 3622(b)(3).
In this case, now that the Commission has had some five years of experience with the Act, the formidable task of definitively interpreting subsection 3622(b)(3) may no longer be deferred. We must first determine whether a thorough examination of the statute bears out our earlier assessment —whether, in short, the Act requires that special efforts be made to trace all the cost consequences of providing the various services and to allocate costs on this basis to the fullest extent reasonably possible. Only then may we evaluate the Commission’s approach for compliance with the Act.
a. Interpreting subsection 3622(b)(3). We begin with the words of the statute. As noted above, subsection 3622(b)(3) requires that “each class of mail or type of mail service bear the direct and indirect postal costs attributable to that class or type plus that portion of all other costs of the Postal Service reasonably assignable to such class or type.”
Three important points are immediately apparent. First, unlike any of the other ratesetting factors contained in section 3622(b), subsection (b)(3) is set forth as a “requirement”, a fact which suggests its special role in the Act’s ratesetting scheme. Second, the section uses words which further emphasize its importance by suggesting a substantial breadth to its coverage. For instance, both attribution and assignment are designed to reach “each” of the classes of mail and types of service. Moreover, not only “direct” but also “indirect” postal costs are to be attributed, and thereafter a portion of “all other costs” of the Postal Service are to be assigned. Third, the emphasis throughout the subsection is unmistakeably upon cost-of-service principles. Under the subsection each service must bear the postal costs “attributable to [it]” and in addition must also bear that portion of all other costs “reasonably assignable to [it]” (emphasis added). Thus, the very words of subsection (b)(3) disclose its concern that each class of mail and postal service shoulder all the postal costs that may reasonably be traced to the provision of that class or service.
Giving the statute a plain reading it seems clear that the first of the subsection’s dual requirements calls for something more than minimal attribution. Had Congress intended, for instance, that cost variability be acceptable as an exclusive method for identifying attributable costs, it in all likelihood would not have given seemingly equal importance to the attribution of indirect, as of direct, postal costs. Strictly speaking, indirect costs may not be attributed by cost variability, at least not by short-term variability; rather, attribution of such costs as a practical matter necessitates the use to some degree of cost allocation formulae based on accounting principles. Moreover, the report of the conference committee confirms the view that Congress intended attribution under subsection 3622(b)(3) to extend beyond minimally attributable costs and to include to a significant extent those additional costs which, although not measurably variable and therefore not directly attributable, may nonetheless be determined with reasonable confidence to be the consequence of providing the service.
A plain reading also clearly suggests that the other costs of the Postal Service that are to be “reasonably assigned” must also be allocated on cost-of-service principles. That is, after the process of extended attribution is complete, a portion of remaining costs are to be assigned to the various mail classes and postal services to the extent that it can reasonably be determined or estimated that certain classes of service may account for particular costs. As discussed above, a primary theme of subsection 3622(b)(3) is its concern with fully tracing the cost consequences of providing the various services. Legislative history, which is explored more thoroughly below, confirms that this theme pertains as much to assignment as to attribution.
One last feature of subsection 3622(b)(3) is disclosed by giving the words of the statute their plain meanings. Congress did not intend that a 11 postal costs be either attributed or assigned. Rather, the statute expressly provides that each class of mail or type of mail service must bear, in addition to its attributable costs, only “that portion of all other costs of the Postal Service reasonably assignable to such class or type” (emphasis added). Thus, some Postal Service costs will exist but will not be “reasonably assignable” to any particular class or type. The other factors enumerated in section 3622 will govern the allocation of these nonattributable and nonassignable costs. This makes good sense. With subsection 3622(b)(3) strengthened from a guideline into the only “requirement” among the eight ratesetting factors listed in section 3622, unless express provision were made for a third category of costs subsection 3622(b)(3) would be susceptible of an interpretation by which all the non-cost factors of the remaining subsections could be read out of the Act. The conference report confirms that Congress acted expressly to prevent just such an interpretation. While clearly the primary purpose of the Act’s ratesetting provision is to assure that attribution and assignment in accordance with cost-of-service principles is carried out to the fullest extent reasonably possible, subsection (b)(3) provides at the same time for a residuum of costs to be used to give effect to the noneost factors expressly set forth in the Act.
Legislative history fully supports the plain reading of subsection 3622(b)(3) and reinforces the conclusion that first and foremost the Act requires that special efforts be made to maximize the use of cost-of-service principles in the allocation of postal costs.
Discrimination in postal ratemaking in favor of certain preferred classes of mail and to the great disadvantage of first class mail has long been a part of our postal system. As early as 1913 the Supreme Court, in Lewis Publishing Co. v. Morgan, 229 U.S. 288, 303-304, 33 S.Ct. 867, 870, 57 L.Ed. 1190 (1913), recognized that Congress designed its postal rate structure to discriminate among classes of mail, conferring “pecuniary advantages of great consequence” upon certain classes of mail, always at the expense of first class, based “upon the conceptions of Congress as to how far it was wise for the general welfare to give advantages to one class not enjoyed by another.” This practice, increasingly more formalized through the years, continued until the time of the Postal Reorganization Act.
In seeking postal reform through the 1970 Act it was a central and express aim of both Houses of Congress to end the abuses of this practice — to get “politics out of the Post Office.” Congress realized that the result of this purposeful discrimination — the setting of rates for some classes of mail well below that necessary to recover the costs of providing the service —was symptomatic of the political process. Debate over the Act discloses that Congress was well aware of the extent to which the availability of preferential rates, and the political nature of postal ratemaking in general, attracted lobbyists into the ratesetting process and invited the abuses that not infrequently result from their influence. A major thrust of the postal reform effort therefore was to minimize this attraction of lobbyist influence by severely curtailing the broad discretion that had characterized pri- or ratesetting procedures and served to shield abuses of the system.
The two Houses advanced different approaches for solving these problems. The Senate passed a bill that would have abolished all rate preferences, phasing in the expected rate increases over five and ten year periods to cushion the impact of the elimination of preferential treatment. The House Bill, on the other hand, would have written into law the preferences then existing by providing that “the preferential rates accorded these categories of mail will not be changed except by Congress, unless the Congress fails to appropriate funds sufficient to cover the revenue foregone because of the rate preference.” Moreover, the two bills differed significantly in the guidelines they prescribed for distributing postal costs to set postal rates: while both proscribed discrimination, the Senate Bill required a reasonable allocation of all costs, including institutional costs, whereas the House Bill provided only that each class of service would bear “at least those costs demonstrably related to [it].”
These differences were subjected to conference bargaining. In exchange for the retention of enumerated preferences, the House accepted the Senate’s standards for allocating costs. Moreover, the standards of the Senate Bill, which in any event were more stringent than those proposed in the House Bill, were further strengthened at conference and expressly made applicable to all classes of mail (§ 3622(b)(3)) including the preferred classes (§ 3626). Subsection 3622(b)(3), which is the only 3622(b) rate-making subsection which was not taken verbatim from the Senate Bill, was originally only a guideline that the Commission, in determining rates, consider “operating costs, the amount of overhead, and other institutional costs of the Postal Service properly assignable to each class of mail or type of mail service.” But when it emerged from conference this guideline had become “the requirement that each class of mail or type of mail service bear the direct and indirect postal costs attributable to that class or type plus that portion of all other costs of the Postal Service reasonably assignable to such class or type.” See note 59 supra.
It is quite apparent from this history that the conference committee amendments to subsection (b)(3) were designed to reemphasize the severe limitations that the Act places upon the Service’s ability to set rates other than in strict accord with cost-of-service principles. Prior to the Act the Service enjoyed broad discretion in the allocation of postal costs, a discretion which in the past had made the setting of postal rates susceptible to political bartering and the frequently abusive influence of lobbyist efforts. We are persuaded that the conference committee amendments, which apparently were insisted upon by the Senate conferees in exchange for the major concession of retaining certain preferential classes of mail, were intended to clarify the extreme degree to which the Act restricts that prior, and quite problemful, discretion. In view of this it would be anomalous to construe subsection 3622(b)(3) as permitting a grudging use of cost-of-service principles which, by expanding the residuum of costs subject to discretionary allocation, simply preserves the potential for continuing the very same discriminatory treatment that the Act so clearly intended to remedy.
Subsection 3622(b)(3) provides, in short, that the Postal Rate Commission must first of all attribute to each mail class or postal service all postal costs which may reasonably be determined, through variability theory as well as through other reasonable inferences of causation, to be the consequence of providing the service. It must then distribute among the mail classes and services that significant portion of all remaining costs of the Postal Service that may reasonably be assigned to each on the basis of best available cost-of-service estimates. The residuum of costs is subject to discretionary allocation in accord with the noncost factors set forth in the Act.
b. Compliance with the Act. In deciding whether the Commission’s adopted ratemaking approach complies with the requirements of the Act we are not unmindful that the scope of our review is limited. Absent a specific statutory command to the contrary our task is simply to ensure that the Commission has followed proper procedures, that it has considered the relevant and excluded the irrelevant, and that its ratemaking order has produced no arbitrary result. As we said in American Publishers, however, we must also be assured that the Postal Service has not “flouted a statutory command.”
The overriding feature of this case is the express mandate of subsection 3622(b)(3) that all reasonable efforts be made to trace the cost consequences of providing each mail class or service and to allocate postal costs on that basis to the fullest extent possible. In specifically requiring that the Commission endeavor to maximize the use of cost-of-service principles, Congress deliberately went beyond the general ratemak-ing requirement that rates be fair and equitable. It is the Commission’s duty therefore to respond faithfully and not grudgingly to this plain command of the statute, and it is equally our duty to carefully scrutinize responses to this particular aspect of the Act’s overall ratesetting scheme and to reject efforts that fail to comply with this special requirement — efforts which, in short, flout the express command of the Act.
(1) Attribution. There is no contention in this case that cost variability is an invalid starting point in the attribution of postal cost — all the parties before us employ it to some extent. The issue rather is whether the Commission’s reliance on cost variability, to the virtual exclusion of other considerations, is insufficiently responsive to the Act’s express concern for extended attribution.
Our task, of course, is not to prescribe an acceptable percentage level of attribution. Nor are we charged with selecting from among alternative approaches available to the Commission the one approach which we deem most responsive to the underlying purposes of the Act. We are an appellate court, not an agency possessed of developed expertise. We look to the design of the Commission’s approach not to substitute our judgment for that of the agency, but only to determine whether the Commission’s adopted method falls unconscionably short of the statutory requirements.
As noted above, the Commission acknowledges that presently incomplete data pre-elude full attribution under its cost variability approach. It insists, however, that utmost accuracy in the measurement of causation must prevail over all else In our view this allegiance to the goal of greatest possible accuracy fatally flaws the design of the Commission’s adopted method since at present the Commission’s goal may be obtained only by substantially disregarding the Act’s express concern for extended attribution.
The Commission suggests, however, that it had no choice but to

Question: What is the most frequently cited title of the U.S. Code in the headnotes to this case? Answer with a number.
Answer:

Answer: 39