Petitions for Review of the Orders of the Illinois Commerce Commission in Ill. C.C. Docket No. 02-0365.
 The opinion of the court was delivered by: Justice Greiman
 Globalcom brought this action against Illinois Bell Telephone Company, d/b/a Ameritech Illinois, now known as SBC Illinois (SBC) before the Illinois Commerce Commission (ICC or Commission). Globalcom alleged that SBC was knowingly engaging in anticompetitive conduct intended to unlawfully restrict competition in the telecommunications market in Illinois. Globalcom's prayer for relief sought injunctive relief, actual damages, attorney fees, and costs. The Commission issued what essentially amounted to a "split decision": it dismissed Globalcom's claims based upon SBC's federal tariff for a lack of jurisdiction, and ruled in favor of Globalcom on only two of its claims based upon an Illinois tariff. SBC has appealed the issues it lost on the merits while Globalcom appeals only in pursuit of greater damages and more attorney fees on the two issues where it prevailed.
 Essentially, this case boils down to an examination of whether SBC knowingly engaged in conduct that was anticompetitive to a rival telecommunications competitor. Specifically, two aspects of SBC's conduct fall under this scrutiny: (1) charging early termination fees to Globalcom due to Globalcom's premature cancellation of a contract with SBC for certain services; and (2) requiring Globalcom to pay rent to store its equipment in an SBC facility as a condition of obtaining a new service from SBC. We conclude that the evidence does not support a finding of liability based upon the imposition of early termination fees. However, we also find the evidence does support a finding of liability for the "rental" requirement SBC imposed upon Globalcom. Accordingly, we reverse in part, affirm in part, and remand the cause to the ICC for a proper redetermination of attorney fees and other incurred costs.
 In May of 2000, Globalcom initiated a fast-track proceeding against SBC pursuant to section 13-514 of the Public Utilities Act (Act) (220 ILCS 5/13-514 (West 2002)). Globalcom claimed that the terms upon which SBC offered a certain combination of unbundled network elements (UNEs), known as an "Enhanced Extended Link" (EELs), were anticompetitive in violation of section 13-514 of the Act. The Commission rejected many of Globalcom's claims, but agreed with Globalcom in two respects.
 SBC's obligation to provide UNEs to competing local exchange carriers (CLECs) arose from the federal Telecommunications Act of 1996 (FCA) (47 U.S.C. §332(c)(7) (2000)). The FCA sought to introduce competition in the local communications market by dismantling "natural monopoly" regulation and creating ways by which CLECs can compete with "incumbent" local exchange carriers like SBC. In short, a CLEC can lease certain "network elements" from the incumbent on an unbundled basis and use them, either in combination with other UNEs or with its own facilities, to provide competitive telephone service.
 The Federal Communications Commission (FCC) has identified the list of network elements that incumbent carriers must unbundle and has issued rules regarding the incumbent's duty to provide combinations of UNE's. Specifically, the FCC required incumbents not to separate combinations of UNEs that are already connected to one another (pre-existing combinations) and to affirmatively combine UNEs for CLECs in some circumstances (new combinations). Two of the units defined by the FCC are the "local loop," a wire which connects a home or business to the incumbent's switch, and dedicated interoffice transport facilities (dedicated transport), which connect various switches to one another. Together, a loop and a dedicated transport facility constitute an EEL. This case involves the terms and conditions on which SBC offered both pre-existing EELs and new EELs.
 In the past, Globalcom leased "special access service" from SBC to connect Globalcom's customers to the network because SBC did not have a tariff to make EELs available. Special access is a dedicated transmission path between two points located within a single state (i.e., between SBC's local exchange network and another carrier, or between an end user location and a carrier's local exchange network). Special access is an SBC retail-based offering with retail-based rates. Consequently, rates associated with special access are much greater than the rate of cost-based UNE combination EELs. Under rules promulgated by the FCC, a special access circuit is classified as "interstate" and governed by SBC's federal tariff if more than 10% of the traffic that travels on that circuit is interstate. Conversely, if less than 10% of the traffic on a circuit is interstate, a carrier may certify that it is intrastate and purchase the circuit under a corresponding Illinois tariff. Globalcom purchased the vast majority of its special access circuits from SBC under the federal special access tariff.
 Both the state and federal tariffs in effect at the time of the Commission's decision provide for an optional payment plan under which a customer can agree to lease special access service for a specified period of time at a discount, rather than on a month-to month basis. Each tariff further provides that "customers requesting termination of service prior to the expiration date of the [optional payment plan] term will be liable for a termination charge." "The termination Charge *** will be calculated as follows: The dollar difference between the current [optional payment plan] rate for the [optional payment plan] term that could have been completed during the term that the service was actually in service, or the monthly rate for services in place less than 12 months, and the customer's current [optional payment plan] rate for each month the service was provided." In other words, if a carrier commits to a certain term of service and then terminates its service before the term is expired, it must pay the difference between the amount that it would have paid if it had correctly stated its term of service and the lesser amount that carrier paid prior to termination.
 According to FCC rules, under the FCA, a CLEC may terminate its lease of a special access circuit from SBC and ask SBC to provide that circuit as an EEL. CLECs can do this if, among other things, they certify that they will use those facilities to provide a significant amount of local exchange service to an end user, and thus compete with SBC. As mentioned above, replacing a special access circuit with an EEL is attractive to CLECs because the FCC's pricing rules for UNE's make an EEL far cheaper than a special access circuit. In Illinois, on June 30, 2001, section 13-801 of the Act (220 ILCS 5/13-801 (West 2000)) became law and obligated SBC to make UNEs, including EELs, available to CLECs.
 In December of 2001, Globalcom asked SBC to terminate its lease of five special access circuits under the federal tariff and to obtain access to the same facilities as EELs. SBC denied the request because the EELs would have been "commingled" with tariffed special access services, in violation of FCC rules. SBC also stated that the termination of the special access circuit prior to the expiration of the optional payment plan term for which Globalcom committed itself would trigger payment of the termination charges under the federal tariff. Globalcom did not challenge SBC's position on "commingling," but also did not want to pay the termination charges. Consequently, Globalcom chose not to pursue the conversion of those circuits.
 On March 14, 2002, Globalcom sent SBC a notice of an alleged violation of section 13-514 of the Act, and then filed its first amended complaint with the ICC on May 16, 2002. Globalcom asserted that the termination charges did not apply under the federal tariff or the Illinois tariff in instances where Globalcom "converted" its purchase of special access and simultaneously obtained access to the same facilities as UNEs for the remaining term.
 The Commission rejected Globalcom's assertions with respect to the "conversion" of the federal special access circuits to UNEs. The ICC's order found that SBC's enforcement of the termination liability provision is "not in derogation of federal law and FCC regulations, and the Commission has no authority to direct SBC Illinois to depart from the terms of federal tariffs." In other words, "FCC tariffs pertain to interstate, not local, telecommunications services and exist exclusively under federal authority." Nevertheless, the ICC held that the termination liability of the Illinois tariff would not apply for the "conversion" of special access circuits to EELs. In so finding, the ICC held that SBC acted "unreasonably" and "knowingly impede[d] the development of competition" by assessing early termination charges under the Illinois tariff.
 As noted, section 13-801 of the Act also required incumbents to make new EELs available to CLECs by combining a loop and a dedicated transport facility that were not already connected. New EELs offer the same discount as pre-existing EELs, but also reduce the number of the incumbent's central offices at which the CLEC must install, or "collocate," its own equipment. As the FCC explained, a new EEL:
 "[A]llows a requesting carrier to serve a customer by extending a customer's loop from the end office serving that customer to a different end office in which the competitor is already collocated. The [new] EEL therefore allows requesting carriers to aggregate loops at fewer collocation locations and increases their efficiencies by transporting aggregate loops over efficient-high capacity facilities to their central switching location. Thus, the costs of collocation can be diminished through the use of the [new] EEL *** [because a CLEC] would need to collocate in as few as one incumbent *** central office *** to provide service." Third Report and Order and Fourth Further Notice of Proposed Rulemaking, Implementation of the Local Competitive Provisions of the Telecommunications Act of 1996, 15 F.C.C.R. 3696, par. 288 (1999) (UNE Remand Order).
 Specifically, section 13-801(d)(3) of the Act directed SBC to provide CLECs with certain UNE combinations from a draft of an interconnection agreement that SBC previously had submitted in another ICC proceeding, identified as "Draft I2A." New EELs were part of the new UNE combinations in the Draft I2A, and the Draft I2A required that a new EEL terminate in a CLEC's collocation arrangement in an incumbent's central office.
 As SBC notes, however, Act section 13-801 was not self-effectuating. Instead, there needed to be some instrument setting forth the specific rates, terms, and conditions on which SBC would offer its various products and services. Accordingly, SBC filed a "compliance tariff" with the ICC on July 2, 2001, the first business day after Act section 13-801 took effect (the permanent tariff). Consistent with Act section 13-801(d)(3), the permanent tariff's provisions on new UNE combinations used the terms and conditions for those combinations in the Draft 12A, including the collocation requirement for new EELs. After allowing over two months for the ICC to review the tariff, the ICC entered an order on September 13, 2001, that suspended the permanent tariff and initiated a docket to review it.
 Thereafter, on September 10, 2001, SBC voluntarily filed its "interim compliance tariff" in accordance with section 13-801 of the Act, pending review of its proposed permanent tariff by the Commission. According to SBC, the express purpose of the interim compliance tariff was to "immediately" make all of the new UNE combinations in the Draft 12A available to all CLECs on the same rates, terms, and conditions (including the collocation requirement) set forth in the Draft 12A and in the proposed permanent tariff. Because SBC ostensibly wanted to make the new UNE combinations available to CLECs as quickly as possible, it asked the ICC to have the interim tariff take effect on less than the usual 45 days' notice. The ICC staff, who had already reviewed the identical terms and conditions in the permanent tariff for two months, "reviewed the tariff again" and found "good cause" for granting SBC's request. The interim tariff took effect on September 18, 2001.
 Less than two weeks prior to its seeking to convert its special access facilities to existing EELs, Globalcom also sought the lease of new EELs. However, SBC did not fill Globalcom's order because Globalcom did not have a collocation arrangement in place and, therefore, was not able to purchase new EELs under the interim tariff. Globalcom also challenged this denial in its complaint to the ICC, claiming that the requirement that new EELs terminate in a collocation arrangement was unlawful and anticompetitive under Act section 13-514.
 However, before the ICC could rule on that complaint, it decided in the permanent tariff investigation that requiring new EELs to terminate in a collocation space violated Act section13-801(d)(3). Globalcom then admitted that decision removed any need for relief in its own complaint case, and the ICC concurred, stating that it "need not resolve" Globalcom's complaint regarding the collocation requirement for new EELs. However, the ICC then ordered SBC to pay damages to Globalcom for having included the collocation requirement in the interim tariff. Specifically, the ICC held that SBC "should have known" that the collocation requirement was unlawful. It concluded: "It should have been apparent to [SBC] in September, 2001, when it filed the Interim Compliance Tariff, that the applicable authorities were not merely devoid of a collocation requirement, but expressly negated it."
 In so holding, the ICC found that SBC must pay damages caused by SBC's collocation requirements to Globalcom for the difference between what Globalcom paid for special access circuits under SBC's valid state tariff and what it would have paid for new EELs had they been available without collocation. However, the Commission limited its damages calculations to only those services ordered from SBC's intrastate special access tariff because it reasoned that it did not have the authority to award damages based on purported violations of federal law. After having ruled on the merits, the Commission then considered the provisions in the Act that authorized it to impose penalties, award attorney fees, and to allocate the Commission's costs of the proceeding among the parties. See 220 ILCS 5/13-515(g), 5/13-516(a)(2), (a)(3) (West 2002). The Commission (i) declined to impose penalties; (ii) awarded Globalcom 50% of its attorney fees; and (iii) ordered Globalcom to pay 25% of the Commission's cost of conducting the proceeding. Both SBC and Globalcom have appealed.
 The issues in this case involve the Commission's interpretation and application of provisions of the Act as well as SBC's tariffs. The Commission's interpretation of a provision of the Act "should only be reversed if it is erroneous." Illinois Bell Telephone Co. v. Illinois Commerce Comm'n, 282 Ill. App. 3d 672, 676 (1996). Moreover, a tariff is a statute, not a contract, and has the force and effect of a statute. Illinois Central Gulf R.R. Co. v. Sankey Brothers, Inc., 67 Ill. App. 3d 435, 439 (1978), citing City Messenger Service of Hollywood, Inc. v. Capitol Records Distributing Corp., 446 F.2d 6 (6th Cir. 1971). Accordingly, when interpreting the applicability of a tariff, "[i]f the Commission's interpretation is not an unreasonable one," the reviewing court will not reverse it. Chicago Housing Authority v. Illinois Commerce Comm'n, 20 Ill. 2d 37, 42 (1960); General Mills, Inc. v. Illinois Commerce Comm'n, 201 Ill. App. 3d 715, 721 (1990).
 However, when reviewing the Commission's factual findings, this court must determine whether they are supported by the evidence, not whether based on that evidence this court would have arrived at the same conclusion as the Commission. Champaign County Telephone Co. v. Illinois Commerce Comm'n, 37 Ill. 2d 312, 320-21 (1967). In other words, the petitioner bears the burden of proof to show that the opposite conclusion is clearly evident. Citizens Utility Board v. Illinois Commerce Comm'n, 291 Ill. App. 3d 300, 304 (1997). Nevertheless, when the Commission drastically departs from past practice, the Commission's decisions are entitled to less deference. Business & Professional People for the Public Interest v. Illinois Commerce Comm'n, 136 Ill. 2d 192, 228 (1989).
 SBC's first argument on appeal is that the Commission erred in finding that its early termination charges did not apply under the Illinois special access tariff for five separate reasons. First, SBC notes that the Illinois special access tariff contained exactly the same language governing termination charges as its federal counterpart which permits the assessment of termination charges in the same circumstances. Further, SBC notes, the Commission previously has upheld the assessment of early termination charges under the Illinois tariff as well. And because the Commission construes the same language in the federal and state tariffs with different results, SBC asserts its holding is arbitrary and capricious.
 At the outset, SBC claims that there can be no doubt that the FCC has upheld the assessment of early termination charges under federal special access tariffs whenever the purchaser terminates the special access service and leases an EEL. It offers the following examples:
 "We note, however, that any substitution of unbundled network elements for special access would require the requesting carrier to pay any appropriate termination penalties required under volume or term contracts." UNE Remand Order, par. 481 n. 985.
 "We reject comments by US LEC/XO that *** early termination penalties *** are obstacles to their ability to convert special access circuits to EELs." Joint Application by BellSouth Corp., 17 F.C.C.R. 9018, par. 200 (2002).
 "[O]ur current rules do not require incumbent LECs to waive tariffed termination fees for carriers requesting special access circuit conversion." Application of Verizon ...