*750OPINION
GILDEA, C.J.Appellant ALLETE, Inc. d/b/a Minnesota Power (“Minnesota Power”) challenges the decision of the Minnesota Public Utilities Commission (“Commission”) setting interim rates. Minnesota Power argues that the Commission exceeded its statutory authority and, in the alternative, that the record does not support the Commission’s decision. Because we conclude that the Commission did not exceed its authority and that the record otherwise supports the Commission’s decision, we affirm.
Minnesota statutes provide the Commission with authority to regulate public utilities in Minnesota, including regulation of the service rates that public utilities charge. See Minn.Stat. §§ 216B.08, 216B.16 (2012). Under this statutory scheme, a public utility cannot change service rates except by filing notice of such rate change with the Commission. Minn.Stat. § 216B.16, subd. 1. On November 2, 2009, Minnesota Power filed a notice with the Commission indicating Minnesota Power’s intent to change its service rates. Minnesota Power sought an increase in rates of $80,885,213 annually, or approximately 18.9 percent. As part of its submission to the Commission, Minnesota Power also filed a petition for an increase in interim rates. Minnesota Power requested an interim rate increase of $73,296,560, or 17.1 percent annually.
Minnesota Power’s petition to increase its rates was resolved through a contested case proceeding. After that process, the Commission set Minnesota Power’s final rate increase at approximately $53.5 million. Minnesota Power does not challenge that decision. Rather, the challenge here is to the Commission’s decision to set the interim rate increase at approximately $48.5 million. Interim rates, which are designed to “protect utilities from the potentially confiscatory effect of regulatory delay,” Henry v. Minn. Pub. Utils. Comm'n, 392 N.W.2d 209, 213 (Minn.1986), are determined by the Commission in an ex parte proceeding and are effective during the contested case process until the new final rates go into effect. Minn.Stat. § 216B.16, subd. 3. Under Minn.Stat. § 216B.16, subd. 3(b), the interim rate “shall be calculated” using the formula set forth in the statute “[u]nless the commission finds that exigent circumstances exist.” 1
Even though the question of an interim rate increase is an ex parte proceeding, respondents Large Power Intervenors, Boise Inc., and the Residential and Small Business Utilities Division of the Office of the Attorney General (“Attorney General”) submitted comments to the Commission generally opposing the amount of Minnesota Power’s proposed rate increase. The Attorney General asserted that “no interim rate increase is ‘just and reasonable’ at this time.” The Attorney General based this argument on the “near-record unemployment rates affecting the Minnesota *751Power service territory” and the fact that Minnesota Power’s customers were “entering into the -winter electric heating season, combined with the recent imposition of higher rates and the threat of interim rates on top of that.”2
Along with this outside input, the Commission also had information provided by Commission staff. With respect to the interim rate, the Commission staff included information on Minnesota Power’s three prior rate case filings, discussed the cost and non-cost factors that could influence the interim rate determination, and considered the comments filed with the Commission. The staff also analyzed whether there was a basis to find exigent circumstances based on the statutory framework and the Commission’s prior practices. In analyzing whether exigent circumstances existed, the staff considered the timing of the rate increase, including the fact that customers were about to get a refund based on overpayment of interim rates during the previous rate case. Additionally, the staff considered the state of the economy and the cost of projects required to maintain reliable service. The staff made no recommendation on whether the Commission should conclude that exigent circumstances under Minn.Stat. § 216B.16, subd. 3(b), were present.
With respect to the amount of the interim rate increase, the staff noted that historically “requests for final rate increases filed by utilities are considerably larger than the final amount approved.” Specifically, the staff noted that in Minnesota Power’s previous two cases, filed in 2008 and 1994, the final rate increases approved were 45 percent and 56 percent respectively of the requested rates. In a 1987 rate case, however, the final rate approved was approximately double what Minnesota Power had requested. The staff also considered a 2008 rate case filed by Xcel Energy in which the final rate awarded was 58 percent of the requested rate. Based on these figures, the staff noted that there could be a “basis to find exigent circumstances based on the actual experience with [Minnesota Power] rate filings, coupled with the state of the economy.” The staff then suggested that the Commission could “limit the interim rate increase to approximately 60% of [Minnesota Power’s] $81 million request for final rate increase,” resulting in an interim rate increase of approximately $48 million, or 11.3 percent more than the previously established rate. Ultimately, however, the staff made no recommendation regarding the amount of the interim rate increase.
The Commission issued an order on December 30, 2009, rejecting Minnesota Power’s request for a $73,296,560 interim rate increase, and instead setting the interim rate increase at $48,531,128, or approximately 60 percent of Minnesota Power’s final rate request. The Commission noted Minnesota Power’s right to recover its cost of service and earn a fair rate of return. The Commission also discussed the statutory refund provision that allows utility customers to receive refunds of interim rates paid where the final rate is lower *752than the interim rate. See Minn.Stat. § 216B.16, subd. 3(c). Ultimately, however, the Commission determined that the statutory refund “may not make some ratepayers whole” because “[h]ouseholds and businesses struggling under the current adverse economic conditions — especially given the magnitude of this rate increase and its nearness in time to the last rate increase — may face economic deprivations, business losses, and even disconnections that an eventual refund would not redress.”
The Commission found, therefore, that the economic conditions combined with the magnitude of the rate increase and the proximity to the previous year’s rate increase constituted “exigent circumstances.” Consequently, the Commission concluded that “the most reasonable and equitable course of action” was to reduce Minnesota Power’s “interim rate increase to $48,531,128.”
In response to the Commission’s order, Minnesota Power filed a letter with the Commission objecting to the Commission’s finding of exigent circumstances and reduction in the requested interim rate. Minnesota Power argued that in reducing the interim rate, the Commission violated due process by prejudging the merits of Minnesota Power’s rate request before conducting an evidentiary hearing. Minnesota Power further contended that the Commission had arbitrarily considered only certain past rate cases, relied on factors outside the proposed test year cost-based statutory formula, and violated environmental policy directives by denying Minnesota Power the means to fully recover mandatory expenditures. Minnesota Power asked the Commission to immediately reconsider its interim rate decision and grant the full interim rate request. The Commission did not reconsider its interim rate decision.
Approximately 11 months later, on November 2, 2010, the Commission issued its final order on Minnesota Power’s application, ultimately setting the final rate increase at $53,530,424 annually. The final rate was approximately $27.3 million less than Minnesota Power requested but approximately $5 million more than the interim rate approved by the Commission. In response, Minnesota Power filed a petition for reconsideration requesting, among other items, “reconsideration of the Commission’s decision that exigent circumstances warranted a reduction in [Minnesota Power’s] right to interim rate recovery.” The Commission denied the petition for reconsideration.
Following the denial of its petition for reconsideration, Minnesota Power sought certiorari review with the Minnesota Court of Appeals. The court of appeals affirmed. In re Minn. Power, 807 N.W.2d 484, 490-91 (Minn.App.2011). The court ruled that “the commission did not err in finding exigent circumstances” and “properly exercised its discretion to set interim rates.” Id. The court held that under the plain language of Minn.Stat. § 216B.16, subd. 3, the statutory formula does not apply when the Commission finds that exigent circumstances exist because the statute creates an exigent circumstances exception to the statutory formula. Minn. Power, 807 N.W.2d at 489. The court further concluded that neither the statute nor Minnesota case law specifically defines “exigent” and that, therefore, the Commission may exercise its discretion to find exigent circumstances unrelated to the statutory formula. Id. at 490. Finally, the court concluded that the Commission “did not err in finding exigent circumstances, and then properly exercised its discretion to set interim rates.” Id. at 490-91. We granted Minnesota Power’s petition for review.
*753’When considering decisions of administrative agencies made in contested cases, we “may reverse or modify” an agency’s decision “if the substantial rights of the petitioners may have been prejudiced because the administrative” determination was:
(a) in violation of constitutional provisions; or
(b) in excess of the statutory authority or jurisdiction of the agency; or
(c) made upon unlawful procedure; or
(d) affected by other error of law; or
(e) unsupported by substantial evidence in view of the entire record as submitted; or
(f) arbitrary or capricious.
Minn.Stat. § 14.69 (2012).3 Minnesota Power generally argues that the Commission’s determination of exigency must be reversed because the Commission exceeded its statutory authority under Minn.Stat. § 216B.16, subd. 3(b), when it considered non-cost factors in determining that exigent circumstances exist. Minnesota Power also argues, in the alternative, that even if Minn.Stat. § 216B.16, subd. 3(b), permits the Commission to examine non-cost factors, the Commission’s conclusion that exigency existed was erroneous. We consider each argument in turn.
I.
We turn first to Minnesota Power’s argument that the Commission exceeded its authority under Minn.Stat. § 216B.16, subd. 3(b). We may “reverse an agency decision if the decision was affected by an error of law.” N. States Power Co. v. Minn. Pub. Utils. Comm’n, 344 N.W.2d 374, 377 (Minn.1984). We apply the de novo standard of review to the question of whether the Commission has exceeded its statutory authority. In re Qwest’s Wholesale Serv. Quality Standards, 702 N.W.2d 246, 259 (Minn.2005); Minnegasco v. Minn. Pub. Utils. Comm’n, 549 N.W.2d 904, 907 (Minn.1996). We “resolve any doubt about the existence of an agency’s authority against the exercise of such authority.” In re Qwest’s, 702 N.W.2d at 259.
Under Minn.Stat. § 216B.16, subd. 3(b), [Ujnless the commission finds that exigent circumstances exist, the interim rate schedule shall be calculated using the proposed test year cost of capital, rate base, and expenses, except that it shall include: (1) a rate of return on common equity for the utility equal to that authorized by the commission in the utility’s most recent rate proceeding; (2) rate base or expense items the same in nature and kind as those allowed by a currently effective order of the commission in the utility’s most recent rate proceeding; and (3) no change in the existing rate design.
Minnesota Power argues that the Commission exceeded its statutory authority when the Commission concluded that “exigent circumstances” existed.
The Commission found an exigency based on three factors: the timing of the rate increase, the size of the proposed rate increase, and the state of the economy. Minnesota Power argues that the statute does not permit the Commission to consid*754er these three factors because exigent circumstances must be tied to cost factors in the statutory formula. In addition, Minnesota Power argues that the size and timing of its requested increase are permitted under Minnesota law, and that the Commission therefore erred in basing the exigency determination on these factors.
For its part, the Commission argues that because the statute places no limits on the circumstances the Commission may consider in determining whether exigent circumstances exist, the Commission is free to consider economic conditions as well as the timing and size of the rate increase. Additionally, the Commission argues that the statute is structured such that exigent circumstances are an exception to the otherwise mandatory statutory formula and consequently the formula is not relevant to the determination of whether exigent circumstances exist. We conclude that the plain language of the statute supports the Commission’s interpretation.
We are to construe the statute “as a whole and the words and sentences therein ‘are to be understood ... in the light of their context.’ ” In re Schmidt v. Coons, 818 N.W.2d 523, 527 (Minn.2012) (quoting Christensen v. Hennepin Transp. Co., 215 Minn. 394, 409, 10 N.W.2d 406, 415 (1943)); see also Eclipse Arch. Grp., Inc. v. Lam, 814 N.W.2d 692, 701 (Minn.2012) (noting that we are to “read and construe the statute as a whole, giving effect wherever possible to all of its provisions, and ‘interpreting] each section in light of the surrounding sections to avoid conflicting interpretations)’ ” (quoting Am. Family Ins. Grp. v. Schroedl, 616 N.W.2d 273, 277 (Minn.2000)). And when a statute contains an exception, the exception “exempts from [the statute’s] operation something that would otherwise be within it.” State v. Goodman, 206 Minn. 203, 207, 288 N.W. 157, 159 (1939).
The grammatical structure of Minn.Stat. § 216B.16, subd. 3(b), indicates that the initial phrase, “[u]nless the commission finds that exigent circumstances exist,” modifies, and therefore is an exception to, the remainder of the sentence, which contains the cost-based statutory formula for an interim rate. The statutory formula for calculating the interim rate, but not the exigent circumstances provision, is modified by the cost factors — rate of return, rate base, and rate design. Minn.Stat. § 216B.16, subd. 3(b). When we interpret subdivision 3(b) as a whole and in context, it is clear that the cost factors, which operate when exigent circumstances do not exist, do not control the Commission’s determination of whether exigent circumstances exist. Minnesota Power’s alternate interpretation, which limits the determination of whether exigent circumstances exist to the factors enumerated in the statute, would mean that the exception for exigent circumstances would overlap with the determination of an interim rate because the same cost-based factors based on the same data would be determinative in all cases. The Legislature has directed, however, that we are to give effect to all provisions in the statute — provisions that control when exigent circumstances exist and provisions that control when an exigency is not present. See Minn.Stat. § 645.16 (2012).
Moreover, that Minnesota law permits Minnesota Power to request an increase of the size at issue here, and further permits Minnesota Power to submit the request just 1 day after the last increase went into effect, does not preclude the Commission from considering these factors when assessing whether exigent circumstances exist under the statute. Nor, as indicated above, is the Commission limited to considering only factors relevant to the utility’s cost of service. If the Leg*755islature intended to limit the factors that the Commission considers when determining an exigency, the Legislature could have done so expressly in section 216B.16, subdivision 3(b). It is not for this court to add words of qualification to the statute. See State v. Carufel, 783 N.W.2d 539, 545 (Minn.2010) (“[T]he court cannot add words to a statute not supplied by the legislature”).
In addition to the language and structure of the statute, our precedent confirms the conclusion that the exigent circumstances provision operates outside of the framework of the statutory formula. We previously indicated that “Minn.Stat. § 216B.16, subd. 3 (1984), does permit departure from the statutory formula when there are exigent circumstances.” In re Peoples Natural Gas Co., 389 N.W.2d 903, 907 (Minn.1986). Further, we contemplated the Commission’s consideration of non-cost factors in the context of an interim rate when we held that “unless [the Commission] can be shown to have relied on certain factors to the extent that clear injustice has resulted or that its legislative authority has been clearly exceeded, the courts may not restrict the scope of matters which [the Commission] may consider in allocating costs among consumers.” In re Inter-City Gas Corp., 389 N.W.2d 897, 901-02 (Minn.1986).
But, Minnesota Power argues, the constitutional due process requirement that rates be sufficient to recover the cost of service must inform the Commission’s discretion in determining whether “exigent circumstances” exist. Minnesota Power cites Bluefield Water Works & Improvement Co. v. Public Service Commission of West Virginia, 262 U.S. 679, 43 S.Ct. 675, 67 L.Ed. 1176 (1923); Hibbing Taconite Co. v. Minnesota Public Service Commission, 302 N.W.2d 5 (Minn.1980); and St. Paul Area Chamber of Commerce v. Minnesota Public Service Commission, 312 Minn. 250, 251 N.W.2d 350 (1977) for this proposition. These cases do not control, however, because they do not address the issue of the recovery of cost of service by interim rates set temporarily as part of a larger administrative process designed to determine final rate levels.4
*756Moreover, Bluefield specifically contemplates the consideration of “all relevant facts” to reach a determination that is “just and right in each case.” 262 U.S. at 691, 43 S.Ct. 675. In Bluefield, the United States Supreme Court addressed the issue of whether a utility provider was receiving a “reasonable return on the value of the property used at the time it is being used” so as to avoid depriving the utility of “its property in violation of the Fourteenth Amendment.” Id. at 690, 43 S.Ct. 675. In determining a “reasonable return,” the Supreme Court stated that ascertainment of a reasonable return and value “is not a matter of formulas, but there must be a reasonable judgment having its basis in a proper consideration of all relevant facts.” Id. (citation omitted) (internal quotation marks omitted). The Court continued by explaining that relevant facts could include, among many considerations, the cost of construction and permanent improvements, the value of stock and bonds, and “the sum required to meet operating expenses,” but stressed that these were “all matters for consideration, and are to be given such weight as may be just and right in each case.” Id. at 691, 43 S.Ct. 675 (citation omitted) (internal quotation marks omitted). Bluefield therefore does not support Minnesota Power’s assertion that the Commission erred in considering factors other than Minnesota Power’s cost of service.
Finally, Minnesota Power argues that if we conclude that the Commission can consider factors unrelated to the utility’s cost of service in determining that exigent circumstances exist, then the scope of the Commission’s authority would be enlarged considerably beyond what the Legislature contemplated. Specifically, Minnesota Power argues that if the statutory formula in section 216B.16, subdivision 3(b), does not cabin the Commission’s interim rate decision-making, then the Commission’s authority to set interim rates is boundless. We disagree.
Although the Commission is not bound by the statutory formula in determining whether exigent circumstances exist, general principles in chapter 216B constrain the Commission’s discretion. The statute requires that “[ejvery rate made, demanded, or received by any public utility ... shall be just and reasonable.” Minn.Stat. § 216B.03 (2012). Further, the statute requires that the Commission give “due consideration to the public need for adequate, efficient, and reasonable service and to the need of the public utility for revenue sufficient to enable it to meet the cost of furnishing the service ... and to earn a *757fair and reasonable return.” Minn.Stat. § 216B.16, subd. 6. Finally, “[a]ny doubt as to reasonableness should be resolved in favor of the consumer.” Minn.Stat. § 216B.03. All of these principles operate to constrain the Commission’s decision-making.
In sum, when we construe the term “exigent circumstances” in Minn.Stat. § 216B.16, subd. 3(b), in context, we conclude that the statutory formula in section 216B.16, subdivision 3(b), does not apply when the Commission determines that exigent circumstances exist. We further hold that the Commission did not exceed its statutory authority by considering factors outside those listed in Minn.Stat. § 216B.16, subd. 3(b), in determining whether exigent circumstances were present in this case.
II.
We turn next to Minnesota Power’s alternative argument that the Commission erred in finding that exigent circumstances exist in this case. We have recognized that decisions of administrative agencies “enjoy a presumption of correctness, and deference should be shown by courts to the agencies’ expertise and their special knowledge in the field of their technical training, education, and experience.” Reserve Mining Co. v. Herbst, 256 N.W.2d 808, 824 (Minn.1977). "While we review legal questions de novo, we review factual determinations made within the scope of the agency’s statutory authority under the substantial evidence standard. In re N. States Power Co., 416 N.W.2d 719, 724 (Minn.1987). To uphold the Commission’s findings under the substantial evidence standard, we “determine whether the agency has adequately explained how it derived its conclusion and whether that conclusion is reasonable on the basis of the record.” Minn. Power & Light Co. v. Minn. Pub. Utils. Comm’n, 342 N.W.2d 324, 330 (Minn.1983).
The Commission determined that “[t]hree extraordinary circumstances combine to create exigent circumstances.” The Commission relied on “the unprecedented size of the proposed rate increase ... the extremely short window (one day) between the effective date of [Minnesota Power’s] last rate increase and this rate increase request; and the worst economic downturn in the past 60 years.” When these factors were considered together, the Commission found that “these factors clearly carry serious potential for rate shock — and even outright hardship — for [Minnesota Power’s] customers.”
Minnesota Power argues that the facts of this case are not so extraordinary as to constitute exigent circumstances under Minn.Stat. § 216B.16, subd. 3(b). Although “exigent” is not defined or expressly limited in Minn.Stat. § 216B.16, the Legislature has instructed that “words and phrases” are to be construed “according to rules of grammar and according to their common and approved usage.” Minn.Stat. § 645.08 (2012); see also S.M. Hentges & Sons, Inc. v. Mensing, 777 N.W.2d 228, 231 (Minn.2010) (“If a statute’s words are clear and unambiguous as applied to an existing situation, we construe the words according to their common and approved usage.”). “Exigent circumstances” is defined as “[a] situation that demands unusual or immediate action and that may allow people to circumvent usual procedures.” Black’s Law Dictionary 227 (9th ed.2009). Similarly, dictionary definitions of exigent include “[requiring immediate action” and “[r]equiring immediate aid or action.” The American Heritage Dictionary of the English Language 622 (5th ed.2011); Merriam-Webster’s Collegiate Dictionary 406 (10th ed.2001). Our case law is consistent with these definitions. We have said that *758the term “ ‘exigent’ bespeaks urgency or emergency.” Peoples Natural Gas Co., 389 N.W.2d at 907 (holding that the utility’s proposed rate increase to only one service class “hardly suggests a pressing need of the type which would justify abandoning the statutory plan for interim rates and taking extraordinary action”).
As these definitions indicate, the question of whether exigent circumstances exist is primarily a factual determination. The Legislature has committed the question of exigency to the Commission as part of the Commission’s interim rate making function. See Minn.Stat. § 216B.16, subd. 3(b) (delegating to the Commission the authority to “find[] that exigent circumstances exist”); see also Minn.Stat. § 216B.03 (requiring the Commission to set rates that are “just and reasonable” and “sufficient, equitable, and consistent in application to a class of consumers”); Minn.Stat. § 216B.08 (“The commission is hereby vested with the powers, rights, functions, and jurisdiction to regulate ... every public utility.... The exercise of such powers, rights, functions, and jurisdiction is prescribed as a duty of the commission.”). Whether exigent circumstances exist within the context of utility interim rate setting therefore “necessarily requires application of the [Commission’s] technical knowledge and expertise to the facts presented.” Minn. Ctr. for Envtl. Advocacy v. Minn. Pollution Control Agency, 644 N.W.2d 457, 464 (Minn.2002) (“A determination whether significant environmental effects result from this project is primarily factual and necessarily requires application of the agency’s technical knowledge and expertise.”); see also In re Review of 2005 Annual Automatic Adjustment of Charges for All Elec. & Gas Utils., 768 N.W.2d 112, 119 (Minn.2009) (holding that “[w]e consider an agency’s expertise or special knowledge when ... application of the regulation is primarily factual and necessarily requires application of the agency’s technical knowledge and expertise to the facts presented” (citation omitted) (internal quotation marks omitted)).
The dissent contends that the determination of whether exigent circumstances exist is not a question requiring application of the Commission’s technical knowledge because it is merely a question of basic arithmetic. The dissent’s conclusion is misguided. Minnesota Statutes § 216B.09, subd. 1, requiring the Commission to fix just and reasonable rates, and Minn.Stat. § 216B.16, subd. 3(b), requiring the Commission to determine whether exigent circumstances exist, mandate not only that the Commission identify the factors that impact the setting of rates and the question of exigency, but also that the Commission determine how those factors impact utility companies and ratepayers and, consequently, how those factors affect the decision on what is a just and reasonable rate. The Commission is also required to balance Minnesota Power’s right to recoup its cost of service and earn a fair rate of return with the public interest in affordable utilities. It is determining the impact of the factors and balancing the competing interests of the utility and the public that require application of the Commission’s experience and technical knowledge of the utility industry, not merely the identification of the factors themselves as suggested by the dissent. See In re Review of 2005 Annual Automatic Adjustment of Charges for All Elec. & Gas Utils., 768 N.W.2d at 119 (holding that the Commission applied its “technical knowledge and expertise to the facts presented” and “the Commissioner’s decision ... should be afforded deference” when “the Commission conducted investigations, reviewed accounting practices, and solicited comments from several agencies and organizations *759involved in the regulatory process” in the course of balancing the interests of the public utility and the public to reach its decision).
Because the question of exigency in this context calls for application of the Commission’s expertise to a primarily factual determination, we accord judicial deference to the Commission’s determination of whether the statutory exigency standard has been met. This deference is well supported by our case law. See, e.g., In re Review of 2005 Annual Automatic Adjustment of Charges for All Elec. & Gas Utils., 768 N.W.2d at 119 (deferring to the Commission’s denial of a variance under natural gas regulatory scheme based on the Commission’s technical knowledge and expertise); Minn. Ctr. for Envtl. Advocacy, 644 N.W.2d at 464 (deferring to the agency’s factual determination whether the statutory standard of “significant environmental effects” was met with regard to timber harvesting project); Cable Commc’ns Bd. v. Nor-West Cable Commc’ns P’ship, 356 N.W.2d 658, 668 (Minn.1984) (holding that we “show[ ] deference to an agency’s conclusions in the area of its expertise”); Quinn Distrib. Co. v. Quast Transfer, Inc., 288 Minn. 442, 448-49, 181 N.W.2d 696, 699-700 (1970) (holding that “determination of public convenience and necessity” by the Public Service Commission was an issue of fact, which warranted “substantial judicial deference to the fact-finding processes of the administrative agency”).5
The Commission discussed three “extraordinary circumstances” that combined “to create exigent circumstances”— the unprecedented size of Minnesota Power’s proposed increase; the fact that Minnesota Power requested the proposed increase only 1 day after the increase in Minnesota Power’s “last rate case went into effect”; and the fact that Minnesota Power’s service territory is “in the grip of a severe economic downturn.” There is no dispute that there is factual support in the record for each of the circumstances that the Commission identified. And while it is possible that the factors cited by the Commission, if considered alone, would not constitute exigent circumstances, the Commission’s determination that these circumstances, when considered together, created an urgent situation satisfies the substantial evidence standard. The Commission adequately explained its determination that exigent circumstances existed and that determination is reasonable based on an examination of the record as a whole. See Minn. Power & Light Co., 342 N.W.2d at 330 (discussing substantial evidence standard). As the Commission found, when the size and timing of the increase is considered against the backdrop of “the current adverse economic conditions,” the requested increase “raises serious concerns about rate shock” for Minnesota Power’s ratepayers. When the record is viewed as a whole and in accord with the presumption of correctness that we afford to agen*760cy determinations within the agency’s area of expertise, we hold that the Commission’s determination of exigent circumstances is not erroneous. See Minn. Power & Light Co., 342 N.W.2d at 330 (noting the “judgmental nature” of Commission findings); Reserve Mining Co., 256 N.W.2d at 824 (holding that agency decisions “enjoy a presumption of correctness”).
III.
Finally, we turn to Minnesota Power’s argument that the Commission erred in setting the interim rate increase at 60 percent of the final rate increase Minnesota Power requested. Specifically, Minnesota Power argues that the Commission’s decision must be reversed because the Commission set interim rates by prejudging the company’s final rate request. The Commission concluded that the “most reasonable and equitable course of action” in this case was to reduce Minnesota Power’s interim rate increase from $73,296,560 to $48,531,128, or approximately 60 percent of its requested final rate increase. When the Commission establishes a reasonable rate of return, it is engaging in a quasi-judicial function that we review under the substantial evidence standard. Henry, 392 N.W.2d at 216; Hibbing Taconite Co., 302 N.W.2d at 9.6 We uphold the Commission’s decision when it is supported by “such relevant evidence as a reasonable mind might accept as adequate to support [the] conclusion.” Reserve Mining Co., 256 N.W.2d at 825. Additionally, we show “substantial judicial deference to the fact-finding processes of the administrative agency” and “the burden is upon the appellant to establish that the findings of the agency are not supported by the evidence in the record, considered in its entirety.”7 Id.
*761Minnesota Power argues that there is not substantial evidence to support the Commission’s determination of the interim rate increase because the Commission supported the decision with evidence unrelated to cost factors in the statutory formula. Minnesota Power further argues that, rather than justifying a lower rate, the economic downturn necessitated a higher rate to mitigate the impact of reduced demand and to recover its cost of service based on costs previously incurred through mandatory capital improvements. The Commission counters that it lawfully set reasonable interim rates because Minn.Stat. § 216B.16, subd. 3, grants the Commission broad discretion to adjust a utility’s interim rate request when exigent circumstances exist. The Commission further argues that it acted in accordance with its precedent and traditional rate-making principles when it considered a variety of evidence and balanced the potential burdens faced by Minnesota Power and its ratepayers.
In determining what factors are properly considered by the Commission, we defer to the “analytical approach” chosen by the agency as “a matter for the agency’s expertise.” Minn. Power & Light Co., 342 N.W.2d at 332. Judicial deference allows the agency to give effect to the “the thrust of the statute,” which “is a balancing of interests.” Peoples Natural Gas Co., 389 N.W.2d at 909. For example, when an agency was required to consider the fairness of an insurance plan and “oversee the reasonableness of ... premiums,” we found that the agency’s decision was not arbitrary and capricious when it acknowledged the feasibility of the proposed change but cited several concerns including legislative intent and considerations of fairness, in reaching its decision. In re Excess Surplus Status of Blue Cross & Blue Shield of Minn., 624 N.W.2d 264, 279-81 (Minn.2001). As in Blue Cross, the Commission here balanced the equities between Minnesota Power and its customers during the economic downturn, cited specific economic concerns, and considered the Legislature’s intent to protect consumers in setting a fair and reasonable interim rate. The Commission specifically recognized that there were two sides to the “exigent circumstances equation” and noted both “the impact of the proposed rate increase on ratepayers” and “the impact on [Minnesota Power] of reducing its interim rates request.” Further, like in Blue Cross, the Commission here relied on the evidence submitted by its staff and applied its “technical expertise developed ... in the exercise of legislatively delegated duties and powers to protect the public interest” from the likely impact of an excessive interim rate increase. Id. at 283.8
*762Considering the record as a whole, we conclude that substantial evidence supports the Commission’s interim rate decision. The record reflects that the Commission considered the evidence contained in Minnesota Power’s rate change filing, the record of Minnesota Power’s previous rate change cases, and the information presented in the public comments regarding the impact of an interim rate increase on Minnesota Power’s customers. Additionally, the Commission balanced the harmful impact of the economic downturn on both Minnesota Power and its ratepayers by adjusting the interim rate increase to make it consistent with the final rate increase Minnesota Power received in its previous two cases. In doing so, the Commission attempted to avoid an excessive burden on the ratepayers while still considering Minnesota Power’s right to charge rates that are sufficient to cover its cost of service and a reasonable rate of return. And, as is directed by the statute, the Commission ultimately placed greater weight on the potentially harmful effect to the consumer of a large rate increase and set the interim rate accordingly. See Minn.Stat. § 216B.03 (instructing the Commission to resolve “[a]ny doubt as to reasonableness ... in favor of the consumer”).
We recognize Minnesota Power’s arguments that the Commission prejudged Minnesota Power’s final rate request and ignored its cost of service in awarding Minnesota Power a lower interim rate than it requested. We disagree with Minnesota Power, however, because there is no evidence that the Commission failed to undertake a full and fair review as required by Minn.Stat. § 216B.16 in determining Minnesota Power’s final rates. Further, Minnesota Power does not challenge the Commission’s final rate determination in this case. Additionally, the evidence shows that the Commission did not ignore Minnesota Power’s cost of service. Although ultimately in this case the interim rate appears to have fallen short of covering Minnesota Power’s cost of service, based on the evidence considered and the process observed, the Commission’s decision is not reversible error under our def*763erential standard of review.9 Reserve Mining Co., 256 N.W.2d at 825-26.
We are not unsympathetic to the statutory asymmetry in Minn.Stat. § 216B.16, subd. 3(c). The statute requires “the utility to refund the excess amount collected under the interim rate schedule, including interest” when “the commission finds that the interim rates are in excess of the rates in the final determination.” Minn.Stat. § 216B.16, subd. 3(c). Under the statute, however, there is no way for a utility to recoup its costs if the interim rate is properly set, but ultimately determined to be lower than the final rate. The question of available remedies under the statute, however, is a matter for the- Legislature.10
Based on this record, we hold that substantial evidence supported the Commission’s decision to set Minnesota Power’s interim rate increase at $48,531,128.
Affirmed.
LILLEHAUG, J., not having been a member of this court at the time of submission, took no part in the consideration or decision of this case.. The statutory formula requires that
the interim rate schedule shall be calculated using the proposed test year cost of capital, rate base, and expenses, except that it shall include: (1) a rate of return on common equity for the utility equal to that authorized by the commission in the utility's most recent rate proceeding; (2) rate base or expense items the same in nature and kind as those allowed by a currently effective order of the commission in the utility's most recent rate proceeding; and (3) no change in the existing rate design.
Minn.Stat. § 216B.16, subd. 3(b). The “proposed test year” used to calculate a utility’s interim rate in Minn.Stat. § 216B.16, subd. 3(b), is based on “the 12-month period selected by the utility for the purpose of expressing its need for a change in rates.” Minn. R. 7825.3100, subp. 17 (2011).
. Minnesota Power objected to the comments. Minnesota Power argued that under Minn. Stat. § 216B.16, subd. 3, the Commission must order interim rates "ex parte without a public hearing” and that under Commission precedent, the Commission "may not consider other parties' comments when setting interim rates.” Before us, Minnesota Power does not argue that the Commission improperly considered the comments because the interim rate decision was to have been made on an ex parte basis. Rather, Minnesota Power argues that the Commission erred in relying on the comments because the comments related to matters that may not be considered under Minn.Stat. § 216B.16, subd. 3(b), when setting interim rates.
. The Commission did not make the decision under review here in a contested case proceeding. See Minn.Stat. § 14.02, subd. 3 (2012) (defining "contested case”). But we have previously applied the standard in Minn. Stat. § 14.69 even though there was not á contested case when the decision under review "involv[ed] application of an agency’s expertise, technical training, and experience” and the parties advocate for the application of section 14.69. Minn. Ctr. for Envtl. Advocacy v. Minn. Pollution Control Agency, 644 N.W.2d 457, 463-64 (Minn.2002).
. The dissent criticizes our distinction of Hib-bing Taconite and St. Paul Area Chamber from the present case on procedural grounds, stating that the “distinction cannot vitiate constitutional requirements.’’ But for purposes of procedural due process, there are critical differences between interim and final rates, as evidenced in the distinction between the interim and final rate processes, the methods for determining interim and final rates, and the purpose for which interim and final rates were created by the Legislature. The interim rate process as described in Minn.Stat. § 216B.16, subd. 3, and Inter-City Gas Corp. is "ex parte" and occurs "without a public hearing," while the final rate "is the object of the entire ratemaking process, a process which fully comports with notions of due process” and may include notice, discovery, and a public hearing. Inter-City Gas Corp., 389 N.W.2d at 902; see also Minn.Stat. § 216B.16, subd. 2. Further, the interim rate schedule reflects only costs and expenses of the "same nature and kind as those finally allowed in the most recent rate proceeding” Inter-City Gas Corp., 389 N.W.2d at 901, while the final rate is prospective and includes consideration of "all relevant facts,” including the utility’s projected future costs. Bluefield, 262 U.S. at 690-92, 43 S.Ct. 675.
The dissent also contends that the Commission failed to operate within the constitutional framework of the Fifth and Fourteenth Amendments in setting the interim rate. The dissent relies on principles applied within the context of final rates. Even if the constitutional framework on which the dissent relies were applicable here, Minnesota Power confirmed at oral argument that it is not claiming that an unconstitutional taking occurred during the 10-month interim rate period. Specifically, counsel for Minnesota Power conceded that Minnesota Power is "not really arguing [that] a constitutional taking” occurred during the 10-month interim rate period at issue in this case. Counsel also con*756firmed that Minnesota Power is not asking us to find in this case that the interim rate was confiscatory. The dissent nevertheless argues that Minnesota Power’s assertion in its petition for review that "the Commission’s decision [was] contrary to law” and "produced a confiscatory effect” is sufficient to preserve a constitutional takings claim. Such a broad standard is not consistent with our precedent. See, e.g., George v. Estate of Baker, 724 N.W.2d 1, 7-8 (Minn.2006) ("A petition for review to this court must specify the legal issues to be reviewed [and we] will generally not address issues that were not specifically raised in the petition for review.” (citations omitted)). Finally, even if Minnesota Power had preserved the constitutional issue, Minnesota Power admitted that it did not introduce evidence of its actual interim rate period costs before the Commission, including costs arising from the decrease in demand for service or environmental mandates. Minnesota Power therefore cannot be said to have sustained its burden of proof such that we could determine whether an unconstitutional taking occurred. See L.A. Gas & Elec. Corp. v. R.R. Comm’n of Cal., 289 U.S. 287, 304-05, 53 S.Ct. 637, 77 L.Ed. 1180 (1933) (holding that "the complainant has the burden of proof” to show that "confiscation is clearly established”). In short, the constitutional question that the dissent reaches out to decide is simply not presented in this case.
. The dissent does not contest our conclusion that the question of exigency is primarily one of fact. Yet, the dissent suggests that the judiciary is equally well-suited to make the exigency determination as the Commission. We disagree. Our precedent recognizes that proper respect for separation of powers principles prevents the judiciary from substituting our judgment for that of the Commission. See In re Excess Surplus Status of Blue Cross & Blue Shield of Minn., 624 N.W.2d 264, 278 (Minn.2001) (explaining that "judicial deference, rooted in the separation of powers doctrine, is extended to an agency decision-maker in the interpretation of statutes that the agency is charged with administering and enforcing” (footnote omitted)); Reserve Mining Co., 256 N.W.2d at 824 (expressing the court’s limited role in reviewing "policy matters which are the responsibility of the legislative and executive branches” and noting that the "fixing of rates” is not a judicial act).
. Minnesota Power and the dissent argue that the Commission's decision was arbitrary and capricious. But in reviewing quasi-judicial decisions of the Commission in setting a just and reasonable rate of return we have applied the substantial evidence standard and reserved the arbitrary and capricious standard for review of rate design determinations. Henry, 392 N.W.2d at 216; Hibbing Taconite Co., 302 N.W.2d at 9. The establishment of a rate of return, which is at issue in this case, requires the Commission to determine based on the submissions of the utility a fair price for the provision of reliable service. See Minn.Stat. §§ 216B.02, subd. 5 (2012); 216B.03; 216B.05 (2012); 216B.16. By contrast, rate design decisions, which are not at issue here, are "the allocation of rates among various classes of utility customers” and are considered "a legislative function.” Hibbing Taconite Co., 302 N.W.2d at 9.
The dissent also argues that we should take a more assertive role or conduct a more vigorous examination of the Commission's decision. Apparently, in order to conduct that more rigorous examination, the dissent would adopt the federal hard look doctrine as defined in Motor Vehicle Manufacturers Ass’n of the United States v. State Farm Mutual Automobile Insurance Co., 463 U.S. 29, 42-43, 103 S.Ct. 2856, 77 L.Ed.2d 443 (1983). The hard look doctrine requires the reviewing court to determine whether the agency "examin[ed] the relevant data and articulated] a satisfactory explanation for its action including a rational connection between the facts found and the choice made.” Id. at 42, 103 S.Ct. 2856 (internal quotation marks omitted) (citation omitted). Minnesota Power does not ask us to apply the federal standard and so the question of whether we should re-examine our standard is not presented in this case. In any event, the standard we apply requires an agency to provide an adequate explanation of how it reached its conclusion and requires the reviewing court to determine whether that conclusion is reasonable. Minn. Power & Light Co., 342 N.W.2d at 330 (noting that in order to uphold the Commission’s findings under the substantial evidence standard, we "determine whether the agency has adequately explained how it derived its conclusion and whether that conclusion is reasonable on the basis of the record”).
. The dissent asserts that the record is inadequate to support the Commission’s consider*761ation of the factors leading to its exigent circumstances determination. As we indicated in Reserve Mining, the burden is on the appellant to establish that the Commission’s findings are not supported by the evidence in the record. 256 N.W.2d at 824-27. Minnesota Power makes no claim that the factors considered by the Commission or the Commission’s findings are not supported by the record. Rather, Minnesota Power contends that it was improper, as a matter of law, for the Commission to consider the factors that it did because those factors are not cost based. The dissent's contention is therefore not at issue in this case.
. The dissent nevertheless contends that the Commission's adoption of an interim rate at 60 percent of Minnesota Power's final rate request should be set aside as arbitrary and capricious. The Commission explained that its decision to set the rate at 60 percent, "an amount slightly in excess of any final revenue requirement found in previous Company rate cases in the last 22 years,” was based on its "balanc[ing] the potential burdens faced by the Company and its ratepayers in light of [the] exigent circumstances, the Company's 22+ years of rate case history, this Commission’s regulatory expertise, and the public interest.” The dissent apparently faults the *762Commission for not considering the fact that in its 1987 rate case, Minnesota Power’s final rate was 193 percent of its initial request. We acknowledge that the Commission appears not to have considered the amount of the rate increase Minnesota Power received in 1987. But that failure does not make its decision arbitrary and capricious when the record reflects that in Minnesota Power's two most recent rate cases, those in 1994 and 2008, the utility received only 45 percent and 56 percent respectively of its initial rate request. See Quinn Distrib. Co. v. Quast Transfer, Inc., 288 Minn. 442, 448-51, 181 N.W.2d 696, 699-701, (1970) (holding that even when there is “a conflict of evidence before the commission” and the evidence was such that the commission could have reasonably reached a contrary decision, the commission's decision was not arbitrary and capricious); cf. Citizens Advocating Responsible Dev. v. Kandiyohi Cnty. Bd. of Comm’rs, 713 N.W.2d 817, 836 (Minn.2006) (holding that when the agency's decision was based on an erroneous and completely unsupported assumption, the decision was arbitrary and capricious); Wajda v. City of Minneapolis, 310 Minn. 339, 343-44, 246 N.W.2d 455, 457-58 (1976) (holding that the city's decision was arbitrary and capricious when it was contrary to the evidence and based solely on speculation arising from prior unrelated acts). Further, the Commission’s decision is distinguishable from Eden Prairie Mall, LLC v. County of Hennepin, cited by the dissent, because unlike in Eden Prairie Mall in which the tax court "failed to exercise its own skill and independent judgment” and simply adopted the County’s valuation of the property, the Commission here did exercise its independent judgment in charting a middle course between Minnesota Power’s full interim rate request and the 0 to 5 percent increase advocated by consumers. 797 N.W.2d 186, 192 (Minn.2011).
. Minnesota Power also argues that by reducing the interim rate to 60 percent of Minnesota Power’s final rate request, the Commission violated its right to procedural due process. Additionally, Minnesota Power contends that the interim rate set by the Commission did not prevent the confiscatory effect of regulatory delay. To the extent that Minnesota Power makes constitutional arguments separate from the statute-based arguments addressed above, such arguments were not preserved on appeal because they were not raised before the court of appeals or in Minnesota Power’s petition for review. We therefore decline to reach these issues. See State v. Koppi, 798 N.W.2d 358, 366 (Minn.2011).
. Because we conclude that the Commission did not err in setting the interim rate, the Commission's order was neither invalid nor unlawful. Minnesota Power is therefore not entitled to recoup the difference between the interim rate and the final rate during the period between when the interim rate became effective and the final rate order. See Qwest’s Wholesale, 702 N.W.2d at 260 (noting that “the [Commission] ha[s] the implied authority to impose a recoupment remedy to compensate a public utility for losses caused by an invalid Commission order”); In re Minnegasco, 565 N.W.2d 706, 711-13 (Minn.1997) (finding that the Commission had implied statutory authority to order recoupment to compensate the utility for lost revenue occasioned by the Commission’s unauthorized imputation of its unregulated affiliated appliance business' revenues to the utility). The dissent would "reverse and remand to the Commission for recoupment proceedings even under our current standard.” But even Minnesota Power admits that recoupment is not available when the Commission acts within its statutory authority but sets an interim rate that is lower than the final rate. Specifically, at oral argument, counsel for Minnesota Power stated that Minnesota Power would have "no remedy” if we determined, as we have above, that the Commission did not err. Nevertheless, the dissent cites what it contends is "broad language of Minnegasco," to support remand. But Minnegasco authorized recoupment only in the case of unauthorized action by the Commission.