dissenting: In this appeal we are asked to determine the legislative intent behind RSA 362-C:3 (Supp. 1990), specifically, whether the legislature intended to require the PUC to analyze the rates under the rate plan negotiated by NU and the State in accordance with existing statutory ratemaking standards. Our decision today will affect electric ratepayers all over New Hampshire for the period remaining under the rate plan and perhaps longer. For the reasons hereinafter set forth, we believe that the majority has incorrectly interpreted RSA 362-C:3 (Supp. 1990) to reach a result that was not intended by the legislature, and, in *166addition, that they have misapprehended federal constitutional rate-making requirements discussed both in federal cases and in the decisions of this court.
I. The Statutory “Just and Reasonable” Standard is Presumed to Apply
Reading RSA 362-C:3 (Supp. 1990) to effectuate one of the legislature’s express purposes in enacting RSA chapter 362-C (Supp. 1990), see 2A N. Singer, Sutherland Statutory Construction § 58.06, at 723 (Sands 4th ed. 1984), it is clear that the PUC was required to determine whether the rates under the rate plan are “just and reasonable.” Although not defined in RSA chapter 362-C (Supp. 1990), “just and reasonable” is a term of art used in RSA 378:7. RSA 378:7, entitled “Fixing of Rates by Commission,” requires the PUC to set “just and reasonable” rates, or rates that are “sufficient to yield not less that a reasonable return on the cost of the property of the utility used and useful in the public service less accrued depreciation.” See RSA 378:27 and :28. According to well established canons of statutory construction, it is assumed not only that the legislature was aware of this statutory “just and reasonable” standard, see Wyatt v. Board of Equalization, 74 N.H. 552, 557, 70 A. 387, 390 (1908) (stating that a statute “must be read in the light of the circumstances then existing,” including “the law as it was then declared”),-but that, by using the term “just and reasonable” when it enacted RSA chapter 362-C (Supp. 1990), the legislature intended this standard to apply-
“ ‘It is assumed that whenever the legislature enacts a provision, it has in mind previous statutes relating to the same subject matter. . . .
Unless the context indicates otherwise, words or phrases in a provision that were used in a prior act pertaining to the same subject matter will be construed in the same sense.’”
Appeal of Town of Hampton Falls, 126 N.H. 805, 809-10, 498 A.2d 304, 307 (1985) (emphasis added) (quoting 2A N. SINGER, SUTHERLAND Statutory Construction § 51.02, at 453-54 (Sands 4th ed. 1984) (footnotes omitted)).
This court further defined the term “just and reasonable” in Appeal of Conservation Law Foundation, 127 N.H. 606, 507 A.2d 652 (1986). In that case, we stated that, given the above-cited statutes, the term “reasonable” or “just and reasonable” rate
*167“must be understood as referring to the result of the rate-making process. The ratemaking process fixes rates that will satisfy a utility’s revenue requirement. Reduced to its essentials, this revenue requirement may be expressed as a formula: R = 0 + (B x r), where R is the utility’s allowed revenue requirement; 0 is its allowed operating expense; B is its rate base, defined as cost less depreciation of the utility’s property that is used and useful in the public service, see RSA 378:27; and r is the rate of return allowed on the rate base.”
Id. at 633-34, 507 A.2d at 671 (emphasis added). The court went on to discuss at some length “both the standard of reasonable rates and the commission’s responsibility in light of that standard.” Id. at 633, 507 A.2d at 671.
There is nothing in either the language or the legislative history of RSA chapter 362-C (Supp. 1990) to rebut the presumption that the legislature intended the phrase “just and reasonable” to refer to the statutory “just and reasonable” standard. The legislature’s use of the phrase “notwithstanding any other provision of law” does not, contrary to what NU and PSNH argue, indicate that it did not intend the statutory “just and reasonable” standard to apply, because this language neither limits nor describes the analysis the PUC was required to undertake in order to assess the reasonableness of the rates under the rate plan. Nor does the fact that the phrase “just and reasonable” appears only in RSA 362-C:l (Supp. 1990), entitled “Declaration of Purpose and Findings,” mean that the legislature was using it in its broader, constitutional sense. It is only logical that this phrase, provided that it is used in the same context, has the same meaning regardless of its location in the statutory scheme. Additionally, the legislative history of RSA chapter 362-C (Supp. 1990) provides no indication that the legislature intended any standard other than the statutory “just and reasonable” standard to apply. Therefore, RSA 362-C:3 (Supp. 1990) required the PUC to determine whether the rates under the rate plan met the statutory “just and reasonable” standard discussed in Appeal of Conservation Law Foundation.
Such an interpretation of the statute does not, as the majority suggests, contravene the legislature’s apparent intent to expedite the resolution of the PSNH bankruptcy. The assumption underlying the majority’s decision is that the legislature wanted to expedite the resolution of the PSNH bankruptcy by ensuring that the PUC would be *168able to approve and implement the agreement, including the rate plan, as quickly as possible. A close look at the plain language of RSA chapter 362-C (Supp. 1990) and its legislative history, however, reveal this assumption to be unfounded.
When it enacted RSA chapter 362-C (Supp. 1990), the legislature stated that the PUC “should be authorized to determine ... whether the rates for electric service to be established [under the rate plan contained in the agreement] . . . should be approved.” RSA 362-C:l, IV (Supp. 1990) (emphasis added). The legislature clearly did not intend the PUC to rubberstamp the rate plan. If the legislature had wanted the rate plan to be approved, it simply could have enacted legislation approving the rate plan. It is well established that the legislature has the authority to set utility rates. See Duquesne Light Co. v. Barasch, 488 U.S. 299, 313 (1989); The Minnesota Rate Cases, 230 U.S. 352, 433 (1913) (stating that “[t]he rate-making power is a legislative power and necessarily implies a range of legislative discretion”). Thus, there was no reason for the legislature to delegate this authority to the PUC, unless it wanted the PUC to use its expertise to analyze the rate plan. The PUC has expertise in determining whether rates are “just and reasonable,” which it has obtained as a result of holding numerous ratemaking proceedings in accordance with the applicable ratemaking statutes. By delegating the authority to approve the rate plan to the PUC without any further instructions, it follows that the legislature intended the PUC to conduct its customary analysis of the rates under the rate plan, whereby it would determine whether the rates met the statutory “just and reasonable” standard. This reading of the statute is consistent with the legislative history of RSA chapter 362-C (Supp. 1990): “This bill authorizes the PUC to conduct a full and complete review of the rate agreement____In other words, it delegates to the PUC the authority to perform an expert review of the technical terms of the Agreement.” N.H.H.R. JOUR. 8 (Special Session, December 14, 1989) (emphasis added).
The legislature desired a prompt resolution of the PSNH bankruptcy, but it desired more. It also wanted to ensure that the rate plan would not unduly burden its ratepayer constituents. A prompt resolution of the PSNH bankruptcy and a careful review of the rate plan in accordance with traditional ratemaking principles were not, however, mutually exclusive goals. Moreover, the enormity of the undertaking involved in this case, namely, the decision whether or not to implement a rate plan calling for seven years of rate increases, warranted a conservative approach in determining the fairness of *169the rate plan, rather than the conclusory treatment engaged in by the PUC. The legislature had sound reason to expect the former; otherwise, it could have adopted the rate plan by statute and shunted the PUC from any participation in this process.
II. The Reasonableness of Rates Must Be Assessed in the Context of the Ratemaking Process
Principles of federal constitutional law also required the PUC to assess the reasonableness of the rates under the rate plan in the context of the ratemaking process. The establishment of “just and reasonable” rates involves a balancing of investor and ratepayer interests, Power Comm’n v. Hope Gas Co., 320 U.S. 591, 603 (1944), which occurs when rates are determined in accordance with traditional ratemaking principles, see Appeal of Conservation Law Foundation, 127 N.H. at 633, 507 A.2d at 671 (stating that the traditional ratemaking process “appropriately balances the competing interests of ratepayers who desire the lowest possible rates and investors who desire rates that are higher”). By determining a proper rate base value and by allowing a reasonable rate of return on that rate base, the PUC ensures that ratepayers do not pay excessive rates and, in addition, guarantees investors an adequate return on their investment. “[W]hether a particular rate is ‘unjust’ or ‘unreasonable’ will depend to some extent on what is a fair rate of return given the risks under a particular ratesetting system, and on the amount of capital upon which the investors are entitled to earn that return.” Duquesne, 488 U.S. at 310.
Although the United States Supreme Court has often stated that there is no constitutionally required ratemaking methodology or formula, Duquesne, 488 U.S. at 316; Colorado Interstate Co. v. Comm’n, 324 U.S. 581, 605 (1945); Hope, 320 U.S. at 602, it must be remembered that in these cases the applicability of the traditional ratemaking process itself was not at issue, but rather some specific aspect of the ratemaking process, for example, rate base. See Duquesne, 488 U.S. at 301-02; Colorado Interstate Co. v. Comm’n, 324 U.S. at 604-05; Hope, 320 U.S. at 603; see also Wisconsin v. Fed. Power Comm’n, 373 U.S. 294, 308-10 (1963) (holding that establishing rates on an area-wide, as opposed to an individual company basis is not unconstitutional); Power Comm’n v. Pipeline Co., 315 U.S. 575 (1942) (upholding the Federal Power Commission’s findings as to rate base, amortization period, amortization interest rate, and rate of return). By stating that there is no single ratemaking formula, the Court apparently meant that there was no required formula for determin*170ing any of the three variables used in the traditional ratemaking process, such as rate base. Accord Appeal of Conservation Law Foundation, 127 N.H. at 637, 507 A.2d at 673 (citing cases). Its holdings should not be read as broadly as the majority suggests, to stand for the proposition that rates may be found to be “just and reasonable,” in the constitutional sense of the phrase, without reference to the traditional ratemaking process. In this instance, “traditional ratemaking process” refers to the general ratemaking process, whereby rates are determined in relation to the proper rate base and rate of return. This process may be expressed as the following formula: R = 0 + (B x r); but use of this specific formula is not necessarily required. See id. at 633, 507 A.2d at 671. What is required is that, in determining whether rates are “just and reasonable,” a utilities commission consider the proper rate base and rate of return, which in this case the PUC failed to do.
In Appeal of Conservation Law Foundation, this court noted that any attempt to determine the reasonableness of rates apart from the general ratemaking process described in that case would entail the risk of unconstitutionality. 127 N.H. at 639, 507 A.2d at 675.
“This is so, not because the State or Federal Constitution guarantees a particular rate, but because existing concepts of the constitutional limits of ratemaking have been developed in the context of a process that does not determine how far to recognize one competing interest in isolation from the other. That process has been described metaphorically as a “constitutional calculus” in which the interests of investors, like the interests of customers, are variables. Consequently, any criterion of reasonableness that might be applied independently from the balancing process that does reflect such interests would run the risk of unconstitutionality by inviting the fixing of rates without regard to the balancing of interests.”
Id. (citations omitted). Similarly, in Company v. State, 95 N.H. 353, 64 A.2d 9 (1949), we stated that
“in the Hope case, as in subsequent decisions called to our attention, the findings of the regulatory body whose orders were sustained disclosed a rational process by which a rate base and a rate of return were determined and applied, to produce the return translated into rates, or in default thereof, the case was remanded for further findings.”
*171Id. at 357, 64 A.2d at 14. Reading the above-cited cases in a consistent manner, they teach us that, although there is no constitutionally required formula for determining rate base, or the other variables used in traditional ratemaking methodology, rates cannot pass constitutional muster unless they have been determined in relation to the proper rate base and rate of return, or in other words, in accordance with the traditional ratemaking process.
III. The PUC’s Analysis of the Rate Plan
In the present case, the comparison made by the PUC between the rates under the rate plan and the estimated traditional rates for the same period was invalid, because the PUC did not properly determine the rates likely under traditional ratemaking methodology. Instead of determining the applicable rate base by calculating the value of PSNH’s prudent investment in property used and useful in the generation of electricity, the PUC assumed the applicable rate base to be $2.3 billion, NU’s acquisition cost of PSNH contained in the agreement. Re Northeast Utilities/Public Service Company of New Hampshire, 114 PUR4th 385, 410 (N.H.P.U.C. 1990). It did so in spite of its previous decision in Re Public Service Co. of New Hampshire, 66 PUR4th 349 (N.H.P.U.C. 1985), in which it stated that
“[reasonable rates on a just and reasonable rate base cannot be finally prescribed without a prudency determination of the capital investment in rate base.
We cannot prejudge the reasonableness of rates or make a definitive finding that rates resulting from the capital investment in Seabrook are unduly burdensome without first finding the prudent investment to which they relate.... We are bound by the New Hampshire and federal Constitutions to assure that ultimately PSNH will receive just compensation through rates on prudent investment. While there are constitutional guarantees of the opportunity to earn a fair return, rates may not be ‘prohibitive, exorbitant, or unduly burdensome to the public.’ The essential reconciliation of prudent investment and reasonable, not unduly burdensome rates may be accomplished in a rate proceeding when PSNH seeks rate support for the addition of Seabrook to its rate base. A prudency investigation should be initiated by the commission on a timely basis to assure an in-depth anal*172ysis of prudent investment and the reasonable rate level for a fair return to investors without unduly burdening ratepayers.”
Id. at 424 (emphasis added) (citations omitted) (quoting S.W. Tel. Co. v. Pub. Serv. Comm., 262 U.S. 276, 290 n.2 (1923) (Brandeis, J., dissenting)).
The PUC arrived at this $2.3 billion figure by finding the value of Seabrook to be $700 million and the value of PSNH’s non-Seabrook assets to be $800 million. The remaining $800 million was labeled as an “acquisition premium.” It does not appear, however, that the $800 million “acquisition premium” represents the value of any particular utility property, so as to be properly included in rate base. See Re Northeast Utilities, 114 PUR4th at 467-68 (the PUC’s rulings on Hydro Intervenors’ requested findings numbers 3 and 7). The $800 million acquisition premium does not legitimately bridge the gap between the value of PSNH’s assets and the price to be paid for PSNH by NU, and is of little solace to a ratepayer who is forced to contribute to a return on that asset which presumably does not generate electricity but merely helps to indemnify junk bondholders. See Appeal of Conservation Law Foundation, 127 N.H. at 650-51, 507 A.2d at 682-83 (King, C.J., and Batchelder, J., dissenting).
Since the PUC did not calculate the applicable rate base value, it was unable to properly determine the rates likely under traditional ratemaking methodology and compare them to the rates that will be produced by the rate plan. Therefore, the PUC erred in approving the rate plan, because it did not properly determine whether the rates that would be established by the rate plan are “just and reasonable.”
IV. Conclusion
In this case, the legislature contemplated, and ratepayers and investors alike were entitled to, a careful and thorough review of the rate plan by the PUC in accordance with traditional ratemaking principles. Yet the PUC, instead of determining whether the rates that New Hampshire ratepayers will be charged under the rate plan are “just and reasonable,” focused its inquiry upon whether the “rate plan yields the minimum rates necessary to finance the payment of the $2.3 billion bankruptcy compromise to PSNH creditors and equity holders without unduly burdening ratepayers or the N.H. economy.” Re Northeast Utilities, 114 PUR4th at 405. Although the PUC cited Appeal of Conservation Law Foundation in its decision, *173apparently it did not fully comprehend the requirements this case imposes. As a result of its cursory analysis of the rate plan, ratepayers may now be unjustly locked into a rate plan which not only provides for seven consecutive years of rate increases totaling, on a cumulative basis, approximately forty-five percent, Re Northeast Utilities, 114 PUR4th at 410, but which contains a return on equity “collar” and “ceiling” which allow for further increases, id. at 418.
The PUC, which five short years ago refused to consider the potential effect of a PSNH bankruptcy, see Appeal of Conservation Law Foundation, 127 N.H. at 670, 507 A.2d at 695-96 (King, C.J., and Batchelder, J., dissenting), in authorizing the further borrowing of hundreds of millions of dollars for the completion of Seabrook Unit I at its then-projected completion cost of $4.7 billion dollars, id. at 648-49, 507 A.2d at 681, has once again fallen short of the mark which the New Hampshire Legislature and ratepayers should reasonably expect of it in the performance of its high constitutional duty. It has found a schedule of rate increases to be in the public good without determining in the first instance whether they are “just and reasonable” as that term has been used by this court, the United States Supreme Court, the New Hampshire Legislature, and its own decisions.
The decision of the court today jeopardizes New Hampshire ratepayers’ interest in receiving adequate utility service at a fair cost, because it results in the establishment of a schedule of electric rates that must be borne by ratepayers over a period of years without an oft-promised prudency hearing concerning PSNH’s investment in Seabrook, see Re Public Service Co. of New Hampshire, 66 PUR4th at 424, which now exceeds $6.5 billion, Re Northeast Utilities, 114 PUR4th at 392 (as of January 1, 1990, the total cost of Seabrook, including all direct costs and interest charges, was approximately $6.5 billion). For the reasons set forth herein, we would remand this matter to the PUC for its appropriate inquiry, and accordingly, we respectfully dissent from today’s per curiam opinion of the court.