Opinion PER CURIAM.
Separate opinion filed by Senior Circuit Judge MacKINNON, concurring in the judgment.
PER CURIAM:This case involves the federal program that imposes fuel efficiency requirements, measured in terms of average miles-per-gallon (mpg), on automobiles and light trucks for model years beginning in 1978. The Center for Auto Safety (CAS) petitions for review of action by the National Highway Transportation Safety Administration (NHTSA) that withdrew an advance notice of proposed rulemaking. That notice, first issued in January 1981 but withdrawn three *844months later, requested public comment on possible improvements in these fuel efficiency standards. Although we conclude that this court has subject matter jurisdiction to review the NHTSA action at issue, we also conclude that the controversy is not yet ripe for judicial review. We therefore dismiss the petition.
I. Background
As a reaction to the energy shortage and resulting economic downturn that followed the oil embargo of 1973-1974, Congress enacted the Energy Policy and Conservation Act, Pub.L. No. 94^163, 89 Stat. 871 (1975). In general terms, the statute was designed “to increase domestic energy supplies and availability; to restrain energy demand; [and] to prepare for energy emergencies.” S.Rep. No. 516, 94th Cong., 1st Sess. 116, reprinted in 1975 U.S.Code Cong. & Ad. News 1762, 1956, 1956. Title III of that statute, known separately as Title V of the Motor Vehicle Information and Cost Savings Act (MVICSA), Pub.L. No. 94-163, § 301, 89 Stat. 871, 901-16 (codified at 15 U.S.C. §§ 2001-2012 (1976 & Supp. V 1981)), established mandatory fuel standards for new passenger automobiles and light trucks beginning with model year 1978. The statute set specific numerical standards for affected vehicles manufactured in model years 1978-1980 and required the Secretary of Transportation or his designee NHTSA to set such standards for the model years from 1981 through 1984. 15 U.S.C. § 2002(a)(1) (1976). Pursuant to this statutory directive, the average fuel economy standard was legislatively set for the years 1978 through 1980 at 18.0 mpg, 19.0 mpg, and 20.0 mpg, respectively, see id., and administratively set for the years 1981 through 1984 at 22.0 mpg, 24.0 mpg, 26.0 mpg, and 27.0 mpg, respectively, see 42 Fed.Reg. 33,534 (1977). All of these recent administrative standards were properly set by the agency and are not being challenged in this case.
For model years 1985 and beyond, however, the MVICSA specifically designates 27.5 mpg as the average fuel economy for the affected vehicles. 15 U.S.C. § 2002(a)(1) (1976). At the same time, subject to congressional approval, the agency “may, by rule, amend the average fuel economy standard ... for model year 1985, or for any subsequent model year, to a level which [it] determines is the maximum feasible average fuel economy level for such model year,” id. § 2002(a)(4). Thus, beginning with model year 1985, the required average fuel efficiency will be 27.5 mpg unless NHTSA decides to modify that standard.
To facilitate the exercise of its discretion for model years 1985 and beyond, NHTSA promulgated an advance notice of proposed rulemaking on January 19, 1981. See 46 Fed.Reg. 8,056 (1981) (hereinafter January Notice). That notice sought public comment from interested parties on the improvements that might be made in future fuel economy standards. The notice carefully stated that its issuance was not intended to indicate that stricter standards necessarily would be established, but rather that its purpose was to gather pertinent information. Specifically, the agency solicited comments relating to available technologies, economics, emission and safety requirements, energy considerations, public choices for the agency, and legislative initiatives for the Congress. These comments were due by April 27, 1981.
On April 6, 1981, however, the White House issued a presidential directive that announced the administration’s intention to withdraw this advance notice of proposed rulemaking. See Office of the Press Secretary, Actions to Help the, U.S. Auto Industry A-35, reprinted in Joint Appendix (JA) 198 (“Because strong market demand for fuel-efficient vehicles is expected to continue, NHTSA believes the initiation of rule-making on post-1985 fuel economy standards to be unnecessary.”). Soon thereafter, NHTSA officially announced withdrawal of the January Notice, see 46 Fed.Reg. 22,243 (1981), essentially relying on three factors to justify the change in policy: (1) that market forces were creating strong consumer demand for fuel efficient cars; *845(2) that manufacturers were responding to those demands and were planning products that would meet fuel efficiency needs; and (3) that any information gathered during April 1981 would prove useless because it would not be current when eventually needed. Finally, NHTSA concluded that, “given the present situation, it is unlikely that the agency will need to commence rulemaking in the foreseeable future.” Id.
CAS promptly petitioned for reconsideration of NHTSA’s decision, asserting that withdrawal of the January Notice was “not supported by the reasons cited, ... unreasonable in light of the expressed purposes and commands of the [statute], and ... not in the public interest.” Letter from Barbara L. Bezdek, Staff Attorney, CAS to Raymond Peck, Administrator, NHTSA (May 16,1981), reprinted in 3A 56-58. The CAS petition argued that relying purely on market forces was contrary to the congressional determination that mandatory standards were needed and that, even if market pressures are effective in this area, the statute requires that the agency consider four factors — technological feasibility, economic practicability, the effect of other motor vehicle standards, and the need of the nation to conserve energy — when determining the maximum feasible average fuel economy to be established, see 15 U.S.C. § 2002(e) (1976).
This petition for reconsideration was denied, both in a lengthy letter to CAS, Letter from Michael M. Finkelstein, Associate Administrator for Rulemaking, NHTSA to Barbara L. Bezdek, Staff Attorney, CAS (Sept. 25, 1981), reprinted in JA 59-62, and in a shorter, yet formal announcement in the Federal Register, see 46 Fed.Reg. 48,383 (1981). In these documents, NHTSA reiterated that market forces were stimulating manufacturers to develop fuel efficient vehicles; indeed, evidence suggested that plans announced by the manufacturers would far exceed the standards already in existence. The agency also contested any claim that it was acting contrary to the statute or the public interest, asserting summarily that “the industry’s ongoing program of new investment . .. will result in meeting consumer demands and fulfilling the Nation’s energy conservation goals in this sector” and that “[a]s long as the demands of the marketplace are being met and these demands fulfill the Nation’s energy conservation goals, the public interest is being served.” Letter from Michael M. Finkelstein at 3-4.
CAS then filed its timely petition for review with this court. A preliminary motion to dismiss was filed by the agency, premised alternatively on this court’s lack of subject matter jurisdiction and on a claim that the petition for review was not yet ripe. By order of this court, that motion was referred to this panel for full briefing and argument together with the merits of CAS’ petition.
II. Subject Matter Jurisdiction
This court, like all courts of appeals, is not a court of general jurisdiction and “[s]uch jurisdiction as it has, to review directly the action of administrative agencies, is specially conferred by legislation relating specifically to the determinations of such agencies made subject to review .... ” American Federation of Labor v. NLRB, 308 U.S. 401, 404, 60 S.Ct. 300, 302, 84 L.Ed. 347 (1940); cf. Califano v. Sanders, 430 U.S. 99, 105, 97 S.Ct. 980, 984, 51 L.Ed.2d 192 (1977) (the Administrative Procedure Act does not provide an independent basis for jurisdiction in the courts of appeals). CAS, therefore, necessarily relies on the judicial review provision of the Motor Vehicle Information and Cost Savings Act to support its claim that this court has jurisdiction to review NHTSA’s decision to withdraw the advance notice of proposed rulemaking. That section of the statute provides in relevant part:
Any person who may be adversely affected by any rule prescribed under section 2001, 2002, 2003, or 2006 of this title may, at any time prior to 60 days after such rule is prescribed ... file a petition in the United States Court of Appeals for the District of Columbia ... for judicial review of such rule....
*84615 U.S.C. § 2004(a) (1976) (emphasis added). NHTSA argues that in issuing and subsequently withdrawing the advance notice of proposed rulemaking, it neither proposed nor established a rule subject to the jurisdiction of this court under this statute. We cannot agree with that construction.
Although section 2004(a) does not itself define “rule,” it does indicate that review of agency decisions by the various courts of appeals is to proceed in accordance with the judicial review provisions of the Administrative Procedure Act (APA). See 15 U.S.C. § 2004(a) (1976) (“the court shall have jurisdiction to review the rule in accordance with chapter 7 of Title 5 [i.e., the APA] and to grant appropriate relief as provided in such chapter”). The APA, 5 U.S.C. § 701(b)(2) (1976), in turn, provides that “rule” is to have the meaning given in 5 U.S.C. § 551(4) (1976):
“rule” means the whole or a part of an agency statement of general or particular applicability and future effect designed to implement, interpret, or prescribe law or policy....
We previously have observed that this definition is broad enough “to include nearly every statement an agency may make .... ” Batterton v. Marshall, 648 F.2d 694, 700 (D.C.Cir.1980) (selection by the Department of Labor of a statistical methodology for analyzing unemployment data is a rule within APA definition); see also Guardian Federal Savings & Loan Association v. FSLIC, 589 F.2d 658, 662, 666 (D.C.Cir.1978); P.A.M. News Corp. v. Hardin, 440 F.2d 255, 258 n. 4 (D.C.Cir.1971). The mere fact that NHTSA did not denominate its withdrawal of the January Notice a “rule” is not determinative of whether it did, in fact, issue a rule within the meaning of the statute. “[I]t is the substance of what the [agency] has purported to do and has done which is decisive.” Columbia Broadcasting System, Inc. v. United States, 316 U.S. 407, 416, 62 S.Ct. 1194, 1200, 86 L.Ed. 1563 (1942); accord Chamber of Commerce of United States v. OSHA, 636 F.2d 464, 467-68 n. 4 (D.C.Cir.1980); Continental Air Lines, Inc. v. CAB, 522 F.2d 107, 124 (D.C.Cir.1975) (en banc).
In withdrawing the January Notice, NHTSA interpreted section 2002(a)(4) as giving it broad discretion to determine whether to modify the fuel economy standards at issue in this case. It also established a policy not to exercise that discretion if market forces were causing automobile manufacturers voluntarily to improve the fuel economy of their products. Furthermore, in denying CAS’ petition for reconsideration, the agency informally concluded that the automobile manufacturers’ plans for voluntarily improving fuel economy were sufficient to meet the nation’s energy conservation goals. These statements accompanying the withdrawal of the January Notice clearly interpret the relevant statute and indicate NHTSA’s policy regarding the exercise of discretion granted to it by that legislative enactment. Given our prior decisions construing the Administrative Procedure Act’s broad definition of “rule,” we are compelled to conclude that NHTSA has prescribed a rule sufficient to grant this court jurisdiction under 15 U.S.C. § 2004(a) (1976).
III. Ripeness
Having determined that NHTSA’s withdrawal of the January Notice and its accompanying justifications constitute a “rule” subject to review in this court, we turn to the question whether the agency action is ripe for judicial review. Although the issuance of a notice of proposed rule-making, or other preliminary proceedings undertaken to promote a proposed rule, often will not be ripe for review because the rule may or may not be adopted or enforced, an agency decision to terminate its rulemaking proceedings usually is ripe for review as final agency action. See, e.g., Professional Drivers Council v. Bureau of Motor Carrier Safety, 706 F.2d 1216 (D.C. Cir.1983); WWHT, Inc. v. FCC, 656 F.2d 807 (D.C.Cir.1981); Natural Resources Defense Council, Inc. v. SEC, 606 F.2d 1031 (D.C.Cir.1979). This is especially true when, as in the present case, the agency explicitly indicates that its decision to ter-*847mínate rulemaking is intended as a means of choosing the status quo over other reasonable alternatives. See 46 Fed.Reg. 22,-243 (1981) (“it is unlikely that the agency will need to commence rulemaking in the foreseeable future”). Thus, to the extent that NHTSA’s public statements withdrawing its January Notice represent a binding decision not to adopt or enforce improved fuel efficiency standards for particular years in the future, but rather represent a decision to maintain the 27.5 mpg standard provided for by Congress, they logically should be ripe for review.
But finality for purposes of judicial review of agency action is to be construed in a “pragmatic way.” FTC v. Standard Oil Co., 449 U.S. 232, 239, 101 S.Ct. 488, 493, 66 L.Ed.2d 416 (1980) (quoting Abbott Laborar tories v. Gardner, 387 U.S. 136, 149, 87 S.Ct. 1507, 1516, 18 L.Ed.2d 681 (1967)). NHTSA therefore argues that, because it has left open the possibility that the agency will initiate new rulemaking proceedings at some, point in the future, see, e.g., 46 Fed. Reg. at 22,243 (“[t]he agency will continue to monitor the effects of the market and the efforts of the manufacturers to improve automobile fuel efficiency”); id. at 48,383, its decision to withdraw the January Notice is nonfinal as to the years covered by the terminated rulemaking. We would, indeed, be hard-pressed to conclude that the agency’s decision to terminate rulemaking for 1995, the last year covered by the January Notice, is ripe for immediate judicial review. Thus, it is necessary to determine for which years covered by the January Notice, if any, NHTSA’s decision to terminate its rulemaking is a final, binding decision— that is, a final decision to leave untouched the statutorily established alternative fuel standard of 27.5 mpg, see 15 U.S.C. § 2002(a)(1) (1976).
We begin by noting that Congress itself has imposed several timing requirements on any change in fuel efficiency standards. First, section 2002(f)(2) of the MVICSA requires that any amendment to the mandatory fuel standards that makes those standards more stringent must be promulgated at least eighteen months prior to the beginning, of the affected model year. 15 U.S.C. § 2002(f)(2) (1976). Thus, amendments to standards for the 1985 model year — which we presume absent contrary evidence to begin during the autumn of 1984 — must be promulgated by early 1983; amendments to standards for the 1986 model year must be promulgated by early 1984; and so on. Second, section 2002(h) requires that these amendments be issued pursuant to the informal rulemaking procedures contained in 5 U.S.C. § 553 (1976), a process that likely will take at least a few months to complete. Thus, the statute has built into its structure a minimum lead time of at least twenty months. By itself, that would make a decision not to amend the 27.5 mpg standard for 1985 model year vehicles a final agency action currently ripe for review. But see infra p. 848.
As for later model years, the record is very much inconclusive. Although CAS argues that several years of lead time are required before automobile manufacturers could meet more stringent fuel efficiency standards, cf. 15 U.S.C. § 2002(a)(3) (1976) (requiring NHTSA to issue standards for model years 1981-1984 by July 1,1977), the statute requires only the eighteen-month period set in section 2002(f)(2) plus time for informal rulemaking under section 2002(h). Moreover, NHTSA has far from conceded any lengthy lead time requirements; indeed, to the extent that manufacturers are already planning to exceed standards currently in existence, and have the technology available to do so, no appreciable lead time beyond that established by the statute would be necessary. Thus, given the limited timing requirements imposed by the statute and no conclusive evidence that longer lead times will be necessary, NHTSA’s decision to withdraw its January Notice and terminate rulemaking for model year 1986 is neither final agency action nor ripe for judicial review until early in the 1984 calendar year. It necessarily follows that NHTSA’s decision is not yet ripe as it relates to subsequent model years. CAS’ *848petition for review, therefore, must be dismissed for model years 1986 and beyond.
As noted above, the agency decision to withdraw the January Notice and thereby maintain 27.5 mpg as the fuel standard for model year 1985 would be ripe for review if such a decision was being challenged. But it is far from certain whether that situation exists in the present case. Each of the documents crucial to the NHTSA action being reviewed vacillate in their description of the exact model years affected by the agency’s decision. For example, the advance notice of proposed rulemaking uses the terms “1985-1995 period” and “post-1985 period” interchangeably. Compare 46 Fed.Reg. at 8,056 with id. at 8,057, 8,061. NHTSA is similarly inconsistent between its'Statement withdrawing the January Notice, see 46 Fed.Reg. at 22,243 (“1985-1995 period”), and its statement denying CAS’ petition for reconsideration, see 46 Fed.Reg. at 48,383 (“post-1985”). Finally, CAS itself demonstrates this inconsistency in its letter petitioning the agency for reconsideration. Compare JA 56 (“after 1985” and “post-1985”) with JA 58 (“in 1985 and later model years”).
Confronted with this uncertainty, if not outright confusion, about the model years affected by the NHTSA actions, the court addressed some specific inquiries to counsel for CAS at oral argument:
Counsel: NHTSA itself initiated a proceeding by issuing an advance notice of proposed rulemaking and invited public input on what would be feasible fuel economy levels to be achieved in the period after 1985.
Court: After when?
Counsel: 1985-1995.
Court: ... Did you say after 1985?
Counsel: Yes, your honor.
Court: Because the records and the briefs wander around on whether if was for 1985 or after 1985.
Counsel: The statutory delegation indicates that the agency has authority to amend the standards for 1985 or the years thereafter.
Court: But the advance notice did not contemplate doing anything for ’85.
Counsel: Yes, your honor.
Oral Argument, Nov. 18, 1982 (emphasis added). Given the uncertainty in the record and briefs presented to the court, this concession that standards for model year 1985 are not being challenged proves telling. Indeed, a challenge by CAS to “post-1985” standards, but not to standards for the 1985 model year, makes perfect sense. The 27.5 mpg standard now set for model year 1985 is already an increase over the 27.0 mpg standard in effect for model year 1984. And CAS has consistently sought a continuously increasing level of fuel efficiency for the affected motor vehicles — a position that is entirely consistent with its concession at oral argument. Thus, the agency action being challenged, though admittedly unclear, focused on model years after 1985 — i.e., exactly those years about which this petition for review is not yet ripe. Given this conclusion, the petition is properly dismissed until such time as judicial review of NHTSA’s decision is more appropriate.
The “basic rationale” behind the ripeness doctrine is “to prevent courts, through avoidance of premature adjudication, from entangling themselves in abstract disagreements over administrative policies, and also to protect the agencies from judicial interference until an administrative decision has been formalized and its effects felt in a concrete way by the challenging parties.” Abbott Laboratories v. Gardner, 387 U.S. 136, 148-49, 87 S.Ct. 1507, 1515, 18 L.Ed.2d 681 (1967). In the present case, NHTSA has made only a preliminary decision not to amend the fuel efficiency standard now in existence for vehicles beginning with model year 1986. Until the beginning of the 1984 calendar year, when the agency’s decision effectively will become final for model year 1986 vehicles, the agency has a' chance, either on its own initiative or in response to another petition for reconsideration, to amend the 27.5 mpg standard or to give better reasons for its *849decision not to do so.* Thus, the agency decision is not yet ripe for review and the petition for review must be dismissed.
It is so ordered.
Without conclusively deciding the issue, we must register our doubts concerning the analysis contained in the concurring opinion, which concludes that NHTSA’s withdrawal of its advance notice of proposed rulemaking is “committed to agency discretion by law.” Such a conclusion fails to realize that, when the agency decision in this case becomes ripe for review, it is because the agency refusal to act effectively maintains 27.5 mpg as the applicable fuel standard for a particular year. Cf. 5 U.S.C. § 551(13) (1976) (defining “agency action” to include “the whole or a part of an agency rule ... or the denial thereof, or failure to act”). Under the statutory scheme established by Congress, such a final decision by NHTSA must determine the “maximum feasible average fuel economy level for such model year,” 15 U.S.C. § 2002(a)(4) (1976), after considering specific factors also listed in the statute, see id § 2002(e)(l)-(4). Thus, NHTSA’s discretion is limited by relevant factors authoritatively established by the Congress. Judicial review to ensure that these factors properly are considered by the agency is the most basic type of court review of administrative action. See Citizens to Preserve Overton Park, Inc. v. Volpe, 401 U.S. 402, 416, 91 S.Ct. 814, 823-24, 28 L.Ed.2d 136 (1971). See generally Note, Judicial Review of Administrative Inaction, 83 Colum.L.Rev. 627 (1983).