The PAEA dictates that the Commission's regulatory system “shall be designed” to achieve nine statutory objectives and “shall take into account” fourteen statutory factors.
39 U.S.C. § 3622(b)–
(c) (reproduced in Appendix,
infra). The Commission established the required “modern system for regulating rates” in November 2007.
See generally Postal Regulatory Comm'n, Order
No. 43,
72 Fed. Reg. 63,662 (Nov. 9, 2007) (the “system regulation”). The part of the system regulation relevant to this case addresses rate adjustments of general applicability.
See 39 C.F.R. pt. 3010, subpart B. Under the system regulation, the Postal Service initiates a proposed rate change by providing notice to the public and to the Commission.
Id. § 3010.10(a). Such notice must be provided at least forty-five days prior to a rate change, and the Postal Service is encouraged to provide as much advance notice as practicable.
Id. § 3010.10. The Postal Service's notice must include, among other things, “[a] discussion that demonstrates how the planned rate adjustments are designed to help achieve the objectives listed in
39 U.S.C. § 3622(b) and properly take into account the factors listed in
39 U.S.C. § 3622(c).”
Id. § 3010.12(b). The notice must also include any “other information” that would assist the Commission in issuing “a timely determination of whether the planned rate adjustments are consistent with applicable statutory policies.”
Id. § 3010.12(b)(12). The Postal Service's notice serves as the proposed rule before the Commission issues a final regulation, i.e., the rate approval order.