In these consolidated appeals, the appellants challenge a decision of the New Hampshire Public Utilities Commission (the PUC) approving a rate plan contained in an agreement relating to the reorganization of Public Service Company of New Hampshire (PSNH) that was negotiated by Northeast Utilities Service Company (NU) and the State. This decision was issued in the PUC’s docket DR 89-244 and reported in Re Northeast Utilities/Public Service Company of New Hampshire, 114 PUR4th 385 (N.H.P.U.C. 1990). The appellants are as follows: Robert C. Richards, Edward Kaufman, and Martin Rochman, who are PSNH stockholders (hereinafter referred to as “the appealing stockholders”); John Hilberg, who is a PSNH ratepayer; and Campaign for Ratepayers Rights (CRR), which is a ratepayer group. The rate plan provides for average base retail rate increases of 5.5% per year for seven years, beginning January 1, 1990, and is an integral part of the agreement whereby NU would acquire PSNH, the State’s largest electric utility, for $2.3 billion. Although the appealing stockholders argue that the average base retail rate increases are too low, and Hilberg and CRR argue that they are too high, both sets of appellants contend that the PUC improperly approved the rate plan without a finding that the rates that would be produced by the rate plan are “just and reasonable” in accordance with traditional ratemaking principles. For the reasons that follow, we affirm the PUC’s decision and dismiss the appeals.
I. Facts and Procedural History
This is an unusual case, in that it involves a public utility that has declared bankruptcy. See Darr, Federal-State Comity in Utility Bankruptcies, 27 Am. Bus. L.J. 63, 64 (1989). PSNH filed for bankruptcy under chapter 11 of the federal Bankruptcy Code on January 28, 1988, citing as the reasons therefor: the magnitude of its investment in Seabrook Nuclear Generating Station Unit 1 (Seabrook); the delay in obtaining licensing approval from the federal Nuclear Regulatory Commission; and its inability to realize any return on its investment until Seabrook went on line, due to the New Hampshire *152Legislature’s enactment of RSA 378:30-a, the so-called “anti-CWIP” law, which prohibits utilities from charging rates that would enable them to recover the cost of “construction work in progress.” Re Northeast Utilities, supra at 391-92.
The bankruptcy court authorized the State to intervene in the proceedings, whereupon the State entered into negotiations with PSNH management and NU, among others, regarding the possible level of rates that could be charged by the reorganized company. Re Northeast Utilities, supra at 392. On November 22, 1989, the State and NU signed an agreement which provided for a merger of PSNH with NU, at an acquisition cost of $2.3 billion, and which included the 5.5% rate plan. Re Northeast Utilities, supra at 392-93.
In a one-day special session held on December 14,1989, the legislature adopted a statute which authorized the PUC to review and implement the agreement. This legislation, RSA chapter 362-C (Supp. 1990), became effective on December 18,1989. The legislature stated that the purpose of the statute was to authorize the PUC
“to determine whether a proposed agreement relating to the reorganization of Public Service Company of New Hampshire and, upon receipt of required regulatory approvals, the acquisition of Public Service Company of New Hampshire by Northeast Utilities, would be consistent with the public good and whether the rates for electric service to be established in connection with the reorganization are just and reasonable and should be approved.”
RSA 362-C:l, IV (Supp. 1990) (emphasis supplied). To effectuate this purpose, RSA 362-C:3 (Supp. 1990) authorized the PUC,
“after hearing, in one or more proceedings to be initiated and completed during the pendency of the Public Service Company of New Hampshire bankruptcy, to determine whether the implementation of the agreement would be consistent with the public good. If the commission so finds, it shall, notwithstanding any other provision of law, establish and place into effect the levels of rates ... in accordance with, and during the time periods set forth in, the agreement.”
(Emphasis supplied.)
Pursuant to this statute, the PUU held hearings on the merits between April 9 and May 5,1990, and hearings on rebuttal and supplemental testimony from May 22 to 25, 1990. Re Northeast Utilities, *153114 PUR4th at 395. Hilberg is the only appellant who was a party to the proceedings before the PUC. In the meantime, the bankruptcy court confirmed NU’s reorganization plan on April 20, 1990, id. at 393, subject to the PUC’s approval of the rate plan. See 11 U.S.C. § 1129(a)(6) (1988) (the bankruptcy court’s confirmation of a reorganization plan is subject to the approval of any rate change provided for in the plan by any governmental regulatory commission with jurisdiction over the rates of the debtor).
Appellants Richards, Kaufman, and Rochman moved separately to intervene in the proceedings before the PUC, but their motions were denied as untimely. Re Northeast Utilities, 114 PUR4th at 395. Appellant Richards thereafter filed a petition in this court, on behalf of himself and appellants Kaufman and Rochman, for a writ of prohibition to the PUC. We denied this petition without prejudice on June 18, 1990. The appealing stockholders are presently appealing the bankruptcy court’s confirmation order in federal district court.
The PUC approved the rate plan in an order issued on July 20, 1990. See id. at 469-70. The order was accompanied by an extensive written decision, in which the PUC explained its analysis of the average base retail rate increases contained in the rate plan and summarized the evidence supporting its findings. It concluded that “the implementation of the Rate Plan as set forth herein is consistent with the public good . .. and will result in just and reasonable rates that equitably balance the interests of ratepayers and investors.” Id. at 460.
The PUC reached its decision after comparing the rate of return to the cost of capital under the rate plan. Id. at 405-08. It also compared the rates under the rate plan with rates forecast for other New England utilities, id. at 411-12, and the rates estimated, insofar as foreseeable, under traditional ratemaking principles, id. at 410-11. The PUC stated that the rates resulting from the use of traditional ratemaking methodology would probably be higher than those provided for by the rate plan, but that it was not required to calculate the precise level of rates under traditional ratemaking principles “to determine whether the Rate Plan serves the public good with just and reasonable rates over the fixed rate period.” Id. at 410. Moreover, it asserted that “[determination of just and reasonable rates by traditional ratemaking methodology, is precluded by the Rate [Plan’s] prescribing the level of retail rates over the seven year fixed rate period.” Id. at 408. The PUC nonetheless estimated the rates that would be achieved under traditional ratemaking principles, insofar as foreseeability permitted. See id. at 410.
*154The appealing stockholders, and Hilberg and CRR, subsequently filed motions for rehearing. The PUC denied their motions on August 17, 1990, and these appeals followed.
II. Standing and Preservation of the Issues
Before reaching the appellants’ arguments, we must first address the contention shared by the State, and NU and PSNH, that the appellants lack standing. For a court to hear a party’s complaint, the party must have standing to assert the claim. 59 Am. Jur. 2d Parties § 30 (1987); see also State ex rel. Thomson v. State Bd. of Parole, 115 N.H. 414, 419, 342 A.2d 634, 637 (1975) (noting that the purpose of the law of standing is to protect against improper plaintiffs). After an administrative agency has denied an individual’s motion for rehearing filed pursuant to RSA 541:3, in order to have standing to appeal the agency’s decision to this court, he must demonstrate that his rights “may be directly affected” by the decision, see RSA 541:3 and :6, or in other words, that he has suffered or will suffer an “injury in fact.” See New Hampshire Bankers’ Ass’n v. Nelson, 113 N.H. 127, 129, 302 A.2d 810, 811 (1973); see also Blanchard v. Railroad, 86 N.H. 263, 264-66, 167 A. 158, 159-60 (1933) (holding that a party to an administrative proceeding does not have standing to appeal an administrative agency’s decision absent a showing of direct injury). Similarly, a party has standing to raise a constitutional issue only when his own personal rights have been or will be directly and specifically affected. 59 Am. Jur. 2d Parties § 33 (1987). Thus, to have standing to appeal the PUC’s decision, the appealing stockholders, and Hilberg and CRR, must demonstrate that they have been “directly affected” by it.
In addition, the appellants must show that the issues raised have been properly preserved for appeal. To appeal a decision or order of the PUC, one must first file a motion for rehearing with the PUC stating “fully every ground upon which it is claimed that the decision or order complained of is unlawful or unreasonable.” RSA 541:4. A party or any person directly affected by the PUC’s decision or order may apply for a rehearing with respect to “any matter determined in the action or proceeding, or covered or included in the order.” RSA 541:3 (emphasis supplied). If the motion for rehearing is denied, the party may then appeal by petition to this court. RSA 541:6. Issues not raised in the motion for rehearing may not be raised on appeal. See RSA 541:4.
*155A. The Appealing Stockholders
Appellants Richards and Kaufman are holders of PSNH common stock. Appellant Rochman is a beneficial owner of PSNH common stock recorded in his wife’s name. Collectively they own 195,000 shares, which is less than one percent of PSNH’s outstanding stock. The appealing stockholders assert that the PUC’s decision approving the rate plan resulted in a violation of their, and PSNH’s, constitutional and statutory rights to recover their “prudent” investment in PSNH plant “used and useful” in the generation of electricity, and that they have been injured, in that the value of their PSNH stock has decreased. They argue that they should be permitted to bring the present appeal in their capacities as individual stockholders or, alternatively, on behalf of PSNH. Because the appealing stockholders have not named PSNH as a party to their appeal, we do not address the issue of whether they have standing to appeal in a derivative capacity. See Kidd v. Traction Co., 72 N.H. 273, 286-88, 56 A. 465, 469 (1903) (stating that a corporation is a necessary party to a derivative action); 13 W. Fletcher, Fletcher Cyclopedia of the Law of Private Corporations § 5997, at 277 (rev. perm. ed. 1984).
In general, a corporation’s board of directors, rather than its stockholders, has the authority to bring an action to redress an injury to the corporation. See 13 W. Fletcher, supra § 5963, at 111. Nevertheless, a stockholder’s rights may be directly affected, entitling him to sue in his individual capacity, “(1) where there is a special duty, such as a contractual duty, between the wrongdoer and the shareholder, [or] (2) where the shareholder suffered an injury separate and distinct from that suffered by other shareholders,” 12B W. FLETCHER , supra § 5911, at 421, or by the corporation itself, Gaff v. Federal Deposit Ins. Corp., 814 F.2d 311, 315 (6th Cir. 1987). A diminution in stock value is an injury that does not fall within either of these two categories and, thus, does not give a stockholder standing to sue on his own behalf. See Dowling v. Narragansett Capital Corp., 735 F. Supp. 1105, 1113 (D.R.I. 1990).
The appealing stockholders have not alleged a direct injury as a result of the PUC’s decision approving the rate plan. Nor have they alleged a constitutional violation of their rights that is distinguishable from a violation of the rights of PSNH or other PSNH stockholders. Accordingly, we hold that they have no standing under RSA chapter 541 to prosecute the present appeal, and, therefore, their appeal is dismissed.
*156B. Appellants Hilberg and CRR
NU and PSNH contend that appellants Hilberg and CRR also lack standing. Specifically, they argue that Hilberg’s status as a ratepayer and the ratepayer status of CRR’s members is insufficient to confer standing, absent a showing by Hilberg that he, and by CRR, that its ratepayer members, have been directly affected by the PUC’s decision. Hilberg and CRR, on behalf of its ratepayer members, allege that the rate increases that will be imposed upon them as a result of the PUC’s approval of the rate plan constitute an “injury in fact” that gives them standing to bring this appeal. In rejoinder, NU and PSNH, citing Blanchard v. Railroad, 86 N.H. 263, 167 A. 158 (1933), maintain that the injury alleged by Hilberg and CRR is no different than an injury to the public in general, and that only the Attorney General and the Office of Consumer Advocate are authorized to represent the public in this instance.
No individual or group of individuals has standing to appeal when the alleged injury caused by an administrative agency’s action affects the public in general, particularly when the affected public interest is represented by an authorized official or agent of the State. See Blanchard v. Railroad, supra at 264-65, 167 A. at 159. This is simply another way of formulating the “injury in fact” or “direct effect” requirement. Similarly, an association has no standing to challenge an administrative agency’s action based upon a “mere ‘interest in a problem.’” Sierra Club v. Morton, 405 U.S. 727, 739 (1972). It does, however, have standing to represent its members if they have been injured. Id.
Unlike the plaintiff in Blanchard v. Railroad, in which “[t]he only interest alleged to have been infringed by the order is that of the public,” supra at 264, 167 A. at 158, Hilberg alleges that he, and CRR alleges that its ratepayer members, will suffer a direct economic injury. Courts in other jurisdictions have held that ratepayers are directly affected by rate decisions and, thus, have standing to challenge them. See Iowa-Ill. Gas & Elec. v. Iowa S. Com. Com’n, 347 N.W.2d 423, 426-27 (Iowa 1984) (citing cases); see also City of Houston v. Public Utility Com’n, 618 S.W.2d 428, 431 (Tex. Civ. App. 1981) (stating that cities, as ratepayers, were “aggrieved” by the public utility commission’s order, in that the increase in electric rates imposed upon them an added financial obligation or burden); Tripps Park v. Pa. Public Utility Com’n, 415 A.2d 967, 970 (Pa. Commw. Ct. 1980) (holding that Tripps Park, an association whose members in-*157eluded utility customers, had standing to appeal a public utility commission rate order). We therefore hold that Hilberg, as a PSNH ratepayer, and CRR, as the representative of its PSNH ratepayer members, have standing to bring this appeal under RSA chapter 541.
NU and PSNH maintain that Hilberg and CRR, even if they have standing to appeal the PUC’s decision, have failed to properly preserve their claims for appeal by raising them in a timely manner. In this appeal, Hilberg and CRR argue first that the PUC erred in approving the rate plan, because it failed to employ the proper analysis to determine whether the average base retail rate increases contained in the rate plan will produce rates that are “just and reasonable”; namely, “traditional ratemaking analysis.” Second, they assert that the PUC was required to consider whether the placement of PSNH’s Seabrook assets into a separate corporation, as provided for by the agreement, would be in the “public good.” Finally, they appear to raise a due process issue in their brief, but this argument is merely a restatement of their first argument that the PUC did not properly analyze the rates under the rate plan in accordance with traditional ratemaking principles. Hilberg and CRR included the first issue, and arguably the third, but not the second, as grounds for their joint motion for rehearing filed with the PUC. NU and PSNH argue that these claims were not properly preserved for appeal, because Hilberg and CRR did not raise them during the PUC proceedings or offer any evidence during the proceedings to support them.
Since Hilberg and CRR did not include the second issue as one of the grounds for their motion for rehearing, they are precluded from raising it on appeal. See RSA 541:4. Additionally, because they made only passing reference to “due process” in their brief, did not cite any constitutional provisions, and did not address this issue during oral argument, we hold that they have not properly preserved the third issue for appeal. See State v. Isaacson, 129 N.H. 438, 439-40, 529 A.2d 923, 924 (1987). However, as to the first issue, we reject NU and PSNH’s argument that Hilberg and CRR are barred from raising it on appeal because they did not raise it during the PUC proceedings or offer any evidence during the proceedings to support it. Hilberg and CRR would have been unable to discover the alleged error made by the PUC, i.e., that it used the incorrect analysis to approve the rate plan, prior to the issuance of the PUC’s decision. Cf. Appeal of Cheney, 130 N.H. 589, 594, 551 A.2d 164, 167 (1988) (stating that parties “are not entitled to take later advantage of error they could have discovered or chose to ignore at the very moment *158when it could have been corrected”). Moreover, this issue is a legal, rather than a factual, one in support of which it was not necessary to introduce additional evidence during the PUC proceedings. Because this issue was discussed by the PUC in its decision and raised in Hilberg and CRR’s motion for rehearing, we hold that it is properly raised on appeal.
To summarize, we hold that the appealing stockholders have no standing to bring the present appeal, and that although Hilberg and CRR have standing, they have failed to preserve for appeal the second and third issues raised in their brief.
The sole remaining issue is whether the PUC erred in approving the rate plan, because it failed to employ traditional ratemaking analysis to determine whether the average base retail rate increases contained in the rate plan will produce rates that are “just and reasonable.”
III. Standard of Review
In addressing this issue on appeal, we apply the standard of review set forth in RSA 541:13. A party seeking to set aside a decision of the PUC has the burden of demonstrating that the decision is unlawful, or, by a clear preponderance of the evidence, that it is unjust or unreasonable. Additionally, findings of fact made by the PUC are presumed to be prima facie lawful and reasonable. RSA 541:13; see Appeal of Cheney, 130 N.H. at 592, 551 A.2d at 166.
IV. The Analysis Required of the PUC
In this case, we are dealing with an issue of the delegation of legislative power. Subject to acknowledged constitutional limitations, considered below, the regulation of utilities and the setting of appropriate rates to be charged for public utility products and services is the unique province of the legislature. Duquesne Light Co. v. Barasch, 488 U.S. 299, 313 (1989); The Minnesota Rate Cases, 230 U.S. 352, 433 (1913); see LUCC v. Public Serv. Co. of N.H., 119 N.H. 332, 340, 402 A.2d 626, 631 (1979). For substantially all of such regulation, the legislature has recognized the need for expertise not readily available as part of legislative resources, and has therefore delegated its power to a standing regulatory commission of the legislature’s creation. RSA ch. 363. The delegated power is exercised in the area of ratemaking, RSA ch. 378, which is conducted through ongoing supervision of rate schedules filed with the PUC. In the traditional ratemaking proceeding, when the utility files for a change in rates under RSA chapter 378, a course of action, well defined by that *159chapter, the PUC’s regulations and the decisions of this court, is undertaken. In the reorganization of PSNH under the State’s agreement with NU, the traditional approach could have been employed, initiated by a PSNH filing for standard and appropriate changes to its existing rates. The rate element of the reorganization could have come to the PUC, in the normal course, under the existing statutory delegation and with all of the judicial requirements attached. However, the rate element of the reorganization was far from traditional, since it envisioned contractual protections for NU, through a contractual guarantee of rates designed to cover the cost of acquisition required to be paid by NU. The contractual rates were intended to be in effect far beyond the period normally and historically appropriate for this utility.
The legislature, citing special needs and circumstances in the situation, RSA 362-C:l (Supp. 1990), saw fit to provide in this statute a special delegation to the PUC of power to review this agreement. RSA ch. 362-C (Supp. 1990). Its delegating charge was for the PUC to “determine whether the implementation of the agreement would be consistent with the public good.” RSA 362-C:3 (Supp. 1990). It charged that, if such a determination is made, “notwithstanding any other provision of law,” the contracted rates shall be established and placed in effect for the contracted period. Id. In exercise of this authority to determine the public good, the legislature authorized the PUC to inquire into “whether the rates for electric service to be established in connection with the reorganization are just and reasonable and should be approved.” RSA 362-C:l, IV (Supp. 1990). The parties disagree as to whether, in such consideration of the rates stipulated by the agreement, by using the phrase “just and reasonable,” the legislature intended the PUC to apply traditional rate-making principles. Hilberg and CRR assert that the statute’s reference to the “just and reasonable” standard, which is also found in existing “traditional” ratemaking statutes, e.g., RSA 378:7 and :28, indicates that the legislature wanted the PUC to undertake a traditional ratemaking procedure, and judge the rates under the rate plan according to established “just and reasonable” standards, or, in other words, to conduct a “traditional ratemaking analysis.” By “traditional ratemaking analysis,” Hilberg and CRR refer to the rate-making process described in Appeal of Conservation Law Foundation, 127 N.H. 606, 507 A.2d 652 (1986).
According to this process, rates are determined using the following formula: R = O + (B x r), where R = required revenue, O = allowed operating expenses, B = rate base and r = rate of return. Id. *160at 633, 507 A.2d at 671; Petition of Public Serv. Co. of N.H., 130 N.H. 265, 270-71, 539 A.2d 263, 266 (1988), appeal dismissed, 488 U.S. 1035 (1989). The PUC first determines the appropriate values of the three variables in the formula: rate base, rate of return, and the utility’s allowed operating expenses. Appeal of Conservation Law Foundation, 127 N.H. at 633-40, 507 A.2d at 671-75. Rate base is defined as ‘“the amount of money that the utility has invested in capital assets (like generating plant and transmission lines) that it uses to provide services to its customers.’” Id. at 634, 507 A.2d at 671 (quoting Glicksman, Allocating the Cost of Construction Excess Capacity: “Who Will Have To Pay For It All?,” 33 Kan. L. Rev. 429, 432 (1985)). It may only include property that is “used and useful” in the generation of electricity, in which the utility’s investment was “prudent” at the time made. Id. at 637-38, 507 A.2d at 673-74. The rate of return, “a percentage applied to the rate base expressed as a dollar amount in order to produce ‘interest on long-term debt, dividends on preferred stock, and earnings on common stock (including surplus or retained earnings),’” id. at 635, 507 A.2d at 672 (quoting C. Phillips, Jr., The Regulation of Public Utilities 332 (1985)), should “yield a return comparable ‘to that generally being made at the same time and in the same general part of the country on investments in other business undertakings which are attended by corresponding risks and uncertainties^]’” Id. (quoting Bluefield Co. v. Pub. Serv. Comm., 262 U.S. 679, 692 (1923)). Once it has determined the values of the three variables, the PUC then calculates the utility’s allowed revenue requirement, from which rates are derived. Id. at 633-40, 507 A.2d at 671-75.
Hilberg and CRR note, quoting Appeal of Conservation Law Foundation, that “any attempt to judge reasonableness [of rates] apart from [the traditional ratemaking] process would . . . risk . . . unconstitutionality.” See id. at 639, 507 A.2d at 674. NU and PSNH, on the other hand, maintain that to interpret RSA 362-C:3 (Supp. 1990) as requiring the PUC to apply these' statutory ratemaking requirements in its analysis of the rate plan would nullify the statute’s purpose, because it would then “be impossible to approve the Rate Agreement.” The State, and NU and PSNH, also argue that traditional ratemaking analysis is not constitutionally required. They contend that even if it were required, the PUC satisfied this requirement by finding that the rate plan would be consistent with traditional ratemaking principles.
We note at the outset that the PUC did estimate, insofar as reasonably foreseeable, what rates would be produced using traditional *161ratemaking methodology, and that it compared these rates to the rates under the rate plan. See Re Northeast Utilities, 114 PUR4th at 410. Hilberg and CRR apparently claim that this comparison was invalid, because the PUC was required to, but did not, conduct a full-blown ratemaking proceeding, as part of which a determination of the “prudent” and “used and useful” value of Seabrook would be made. We base our discussion on this characterization of their argument.
A. Under RSA 362-C:3
To resolve Hilberg and CRR’s argument that RSA 362-C:3 (Supp. 1990) obligated the PUC to apply traditional ratemaking principles in its analysis of the rates under the rate plan, “principles of statutory interpretation require us to look first to the statutory language itself,” Petition of Jane Doe, 132 N.H. 270, 276, 564 A.2d 433, 438 (1989), for the words used in the statute are the best indication of legislative intent. See Chambers v. Geiger, 133 N.H. 149, 152, 573 A.2d 1356, 1357 (1990). When possible, a statute will be interpreted in a manner consistent with its plain meaning. Petition of Jane Doe, 132 N.H. at 276-77, 564 A.2d at 438. “We also examine a statute in relation to the statutory scheme.” State v. Taylor, 132 N.H. 314, 318, 566 A.2d 172, 174 (1989).
The operative section of RSA chapter 362-C, section 3, provides:
“The commission is authorized ... to determine whether the implementation of the agreement would be consistent with the public good. If the commission so finds, it shall, notwithstanding any other provision of law, establish and place into effect the levels of rates ... in accordance with, and during the time periods set forth in, the agreement.”
(Emphasis supplied.) In making this determination of consistency with the public good, RSA 362-C:3 (Supp. 1990) authorizes the PUC to determine whether the rate plan contained in the agreement will produce rates that are “just and reasonable and should be approved.” Since this consideration is specifically mentioned in RSA 362-C:l, IV (Supp. 1990), it is essential to the operative determination of public good. State v. Perra, 127 N.H. 533, 537, 503 A.2d 814, 816-17 (1985) (stating that statutes shall be interpreted to effectuate the legislature’s expressed intent). RSA 362-C:3 (Supp. 1990) does not, however, expressly require the PUC to undertake any particular analysis of the rate plan.
Hilberg and CRR argue that, because the legislature in its declaration of purpose and findings specifically used the phrase “just and *162reasonable,” a term of art found in traditional ratemaking statutes, it intended the PUC to use traditional ratemaking analysis to assess the rates under the rate plan.
It does not follow from the fact that the phrase “just and reasonable” is used in traditional ratemaking statutes that these statutes apply in the present case. In Petition of Public Service Co. of New Hampshire, a case decided subsequent to our decision in Appeal of Conservation Law Foundation, we stated that in the constitutional sense of the phrase,
“[a] just and reasonable rate is one that, after consideration of the relevant competing interests, falls within the zone of reasonableness between confiscation of utility property or investment interests and ratepayer exploitation.”
130 N.H. at 274, 539 A.2d at 268. Thus, we have recognized two “just and reasonable” standards: a statutory standard and a broader, constitutional standard. The question that remains is whether the legislature intended the statutory “just and reasonable” standard to apply in addition to the constitutional “just and reasonable” standard.
It is significant that the only place the phrase “just and reasonable” appears in RSA chapter 362-C (Supp. 1990) is in its “Declaration of Purpose and Findings,” RSA 362-C:l (Supp. 1990), and not in RSA362-C:3 (Supp. 1990), the operative section. That the legislature used the phrase only in the declaration of purpose and findings section is consistent with a determination that it was using the phrase in the broader, constitutional sense, rather than in the more specific, statutory sense. The legislature’s omission of the phrase “just and reasonable” from RSA 362-C:3 (Supp. 1990), entitled “Action by the Commission,” indicates that the legislature did not intend to require the PUC to undertake traditional ratemaking analysis. Had the legislature intended the PUC to do so, it could easily have made this an express requirement. It is not the function of this court to add provisions to the statute that the legislature did not see fit to include. Sigel v. Boston & Maine R.R., 107 N.H. 8, 23, 216 A.2d 794, 805 (1966). Furthermore, the legislature’s mandate that, having determined public good, the contracted rates are to be implemented as agreed, “notwithstanding any other provision of law,” calls more for contract review and ratification than for creative ratemaking.
Interpreting RSA 362-C:3 (Supp. 1990) so as to require the PUC to use traditional ratemaking analysis would also directly contravene the express intent of the legislature in enacting RSA chapter 362-C *163(Supp. 1990). Cf. Quality Carpets, Inc. v. Carter, 133 N.H. 887, 889, 587 A.2d 254, 255 (1991) (stating that “[w]e will construe statutes ‘so as to effectuate their evident purpose’” (quoting State v. Sweeney, 90 N.H. 127, 128, 5 A.2d 41, 41 (1939))). The legislature stated the following as reasons for its enactment of RSA chapter 362-C (Supp. 1990):
“I. The health, safety and welfare of the people of the state of New Hampshire and orderly growth of the state’s economy require that there be a sound system for the furnishing of electric service.
II. The bankruptcy of the state’s largest electric utility, Public Service Company of New Hampshire, has threatened the adequacy, reliability and cost of electric service.
III. The present and predicted growth in electric service demands in the state of New Hampshire requires a prompt resolution of the bankruptcy and reorganization of Public Service Company of New Hampshire.”
The predominant purpose of RSA chapter 362-C (Supp. 1990) was to expedite the resolution of the PSNH bankruptcy by authorizing the PUC, upon a finding of public good, to approve and implement the agreement, which would resolve the PSNH bankruptcy by providing for a reorganization of the utility.
An effort at traditional ratemaking would involve a complex process which, as we noted above, consists of a number of steps. See Appeal of Conservation Law Foundation, 127 N.H. at 633-40, 507 A.2d at 671-75. If RSA 362-C:3 (Supp. 1990) were interpreted as Hilberg and CRR suggest, the PUC essentially would be required to hold a ratemaking proceeding which could take as long as one or two years. See C. Phillips, Jr., The Regulation of Public Utilities 732 (1985) (stating that “‘[fjrom start to finish, the proceedings averaged more than ... 21 months for ratemaking.’” (quoting 4 SENATE Comm. on Governmental Affairs, Study on Federal Regulation, 95th Cong., 1st Sess. 7 (1977))). As a consequence of this interpretation of RSA 362-C:3 (Supp. 1990), the resolution of the PSNH bankruptcy would be delayed rather than expedited, a result that was clearly not intended by the legislature. Further, the agreement was not an appropriate subject for traditional ratemaking. Its contractual nature, its stipulated rate base and its extended term would have made traditional ratemaking a sham or exercise in futility.
*164Based upon the foregoing analysis, we hold that RSA 362-C:3 (Supp. 1990) did not require the PUC to analyze the rate plan in accordance with traditional ratemaking principles. By using the phrase “just and reasonable,” the legislature referred to the constitutional “just and reasonable” standard, rather than the “just and reasonable” standard found in traditional ratemaking statutes, applicable to traditional ratemaking procedures, and discussed in Appeal of Conservation Law Foundation.
B. Under Constitutional Law
Hilberg and CRR also appear to argue that the PUC was constitutionally required to apply traditional ratemaking analysis. Again, they cite Appeal of Conservation Law Foundation as authority. In Appeal of Conservation Law Foundation, we noted that “any attempt to judge reasonableness [of rates] apart from [the traditional ratemaking] process would ... risk... unconstitutionality.” 127 N.H. at 639, 507 A.2d at 674. We did not, however, foreclose the possibility that there existed other constitutionally permissible means of determining “just and reasonable” rates, nor should our holding in that case be construed as unconditionally requiring the use of that traditional ratemaking methodology.
A holding that the use of that traditional ratemaking formula is constitutionally required would be contrary to well-established federal constitutional case law. In Federal Power Commission v. Hope Natural Gas Co., 320 U.S. 591 (1944), the seminal case in this area, the United States Supreme Court held that the Federal Natural Gas Act, 15 U.S.C. § 717 (1988), does not require the use of any particular formula in determining rates. Id. at 602. The Court stated that the methodology used to set rates is irrelevant. See id. Instead, it is the result reached that is important: “[i]f the total effect of the rate order cannot be said to be unjust or unreasonable, judicial inquiry ... is at an end.” Id. Although the Court decided the case under the Federal Natural Gas Act, it noted that “there are no constitutional requirements more exacting than the standards of the Act.” Id. at 607.
The holding in Hope has been followed in numerous subsequent Supreme Court cases. In Wisconsin v. Federal Power Commission, 373 U.S. 294 (1963), the Court stated:
“[T]o declare that a particular method of rate regulation is so sanctified as to make it highly unlikely that any other method could be sustained would be wholly out of keeping *165with this Court’s consistent and clearly articulated approach to the question of the [Federal Power] Commission’s power to regulate rates. It has repeatedly been stated that no single method need be followed by the Commission in considering the justness and reasonableness of rates. ”
Id. at 309 (emphasis supplied). Most recently, in Duquesne Light Co. v. Barasch, 488 U.S. 299 (1989), the Court reaffirmed the principle that “‘[i]t is not the theory, but the impact of the rate order which counts.’” Id. at 314 (quoting Hope, 320 U.S. at 602); see also Petition of Public Serv. Co. of N.H., 130 N.H. at 275, 539 A.2d at 268 (stating that the Federal Constitution is concerned with only the end result of a rate order). Accordingly, the PUC was not constitutionally required to apply traditional ratemaking principles in its analysis of the rates under the rate plan.
V. Conclusion
In conclusion, we hold that RSA 362-C:3 (Supp. 1990) did not obligate the PUC to analyze the rate plan in accordance with traditional ratemaking principles, nor would such methodology be practical or consistent with the legislative delegation. Further, we hold that traditional ratemaking analysis was not constitutionally required in this case. Since Hilberg and CRR neither argue nor demonstrate that the total effect of the rate plan is unjust or unreasonable, we hold that they have failed to sustain their burden of proof to show that the PUC’s decision approving the rate plan was unlawful or unreasonable. Therefore, the PUC’s decision must be affirmed. See Appeal of Cheney, 130 N.H. at 592, 551 A.2d at 166.
Affirmed; appeals dismissed.
Brock, C.J., and Batchelder, J., dissented.