Full Opinion

2026 IL App (1st) 232256 No. 1-23-2256 SIXTH DIVISION October 16, 2026 ______________________________________________________________________________ IN THE APPELLATE COURT OF ILLINOIS FIRST DISTRICT ______________________________________________________________________________ MARK WANCKET, KIMBERLY BEACHY, SALLY ) Appeal from the CRAY, CARL HOLMAN, ELIZABETH MINDER, ) Circuit Court of TERALANDUR VENKATESH, AND DENNIS Cook County. ) WILLIAMS, ) No. 22 CH 11560 Plaintiffs-Appellants, ) ) v. Honorable ) Michael T. Mullen, STATE EMPLOYEES’ RETIREMENT SYSTEM OF ) Judge, presiding. ILLINOIS and BOARD OF TRUSTEES OF THE STATE ) EMPLOYEES’ RETIREMENT SYSTEM OF ILLINOIS, ) Defendants-Appellees. ) JUSTICE PUCINSKI delivered the judgment of the court, with opinion. Justices Hyman and C.A. Walker concurred in the judgment and opinion. OPINION ¶1 I. INTRODUCTION ¶2 This case presents an issue of first impression regarding the meaning of “lump sum salary payments,” as outlined in section 14-103.10 (40 ILCS 5/103.10 (West 2022)) under the Illinois Pension Code, in relation to section 14-108 (id. § 14-108). We are asked to determine whether No. 1-23-2256 bimonthly payments made by respondent for accumulated unused vacation and sick time are included as compensation in the calculation of a state employee’s final average compensation used to determine their retirement annuity under section 14-103.12 of the Pension Code (id. § 14-103.12) or whether they are excluded as “lump sum salary payments” (see id. § 14- 103.10) pursuant to Pension Code section 14-108. ¶3 The amount of retirement annuity that a retiree receives is derived from their final average compensation. See id. § 14-108. Final average compensation means “the monthly compensation obtained by dividing the total compensation of an employee during the period of: (1) the 48 consecutive months of service within the last 120 months of service in which the total compensation was the highest, or (2) the total period of service, if less than 48 months, by the number of months of service in such period; provided that for purposes of a retirement annuity the average compensation for the last 12 months of the 48-month period shall not exceed the final average compensation by more than 25%.” Id. § 14-103.12(a). ¶4 Compensation is defined as follows: “For periods of service on and after January 1, 1978, all remuneration for personal services performed defined as ‘wages’ under the Social Security Enabling Act, including that part of such remuneration which is in excess of any maximum limitation provided in such Act, and including any benefits received by an employee under a sick pay plan in effect before January 1, 1981, but excluding lump sum salary payments: (1) for vacation, (2) for accumulated unused sick leave, 2 No. 1-23-2256 (3) upon discharge or dismissal, (4) for approved holidays.” (Emphasis added.) Id. § 14-103.10(b). ¶5 We find that the bimonthly payments for (i) vacation and (ii) accumulated unused sick leave are “lump sum salary payments” as installment payments towards a known and definite sum owing and are thus properly excluded from the meaning of “compensation” under section 14-108. The plural term “payments” entails the possibility that multiple installments are made toward the enumerated payment categories, which themselves have historically been treated as lump sums. Petitioners’ interpretation of “lump sum” in isolation, although supported by dictionary definitions, is unsustainable, as it conflicts with the broader statutory text and scheme and leads to absurd results. Thus, we affirm. ¶6 II. BACKGROUND ¶7 Plaintiff-appellants Mark Wancket, Sally Cray, Elizabeth Minder, Teralandur Venkatesh, Dennis Williams, Kimberly Beachy, and Carl Holman are retired former employees of the Illinois State Board of Education (ISBE). Each plaintiff-appellant receives a pension from the state through the State Employees’ Retirement System (SERS), administered by the Board of Trustees (Board). Each of the appellants seeks review of final administrative decisions issued by the Board that held that accelerated vacation and sick day payments should be excluded from SERS’ calculation of final average compensation for the purposes of calculating pensions under section 14-103.10 (id. § 14-103.10). ¶8 The petitioners generally fall into three categories. From least-recently to most-recently retired: (1) Mark Wancket, Teralandur Venkatesh, and Dennis Williams seek review of agency decisions reducing their pensions (counts I, VI, VII); (2) Sally Cray and Elizabeth Minder seek review of agency decisions reducing their pensions and directing them to pay back pension 3 No. 1-23-2256 overpayments pursuant to section 14-148.1 of the Pension Code (id. § 14-148.1) (permitting SERS to seek recovery for overpayment when the error was discovered within three years) (counts III, V); and (3) Kimberly Beachy and Carl Holman seek a review of agency decisions that excluded accelerated vacation and sick day payments in the calculation of their pension benefits (counts II, IV). ¶9 Although the posture between the individual appellants varies, they all raise the same question: Does the Pension Code exclude compensation for vacation time and accumulated unused sick leave, made across several payments, from the calculation of an employee’s “final average compensation” when calculating pension annuities under the Pension Code? SERS maintains that payments for vacation and accumulated unused sick leave are “lump sum salary payments” (see id.§ 14-103.10) excluded from the final average compensation calculation under section 14-103.12 (id. § 14-103.12). Appellants argue that payments for vacation and sick leave are not excluded “lump sum salary payments” when they are made in installments. ¶ 10 Since each petitioner’s claim implicates the same legal issue, rather than litigate each retiree’s administrative review claims individually, the parties have briefed and argued the case based on the facts of Wancket’s case. ¶ 11 Wancket’s Case ¶ 12 Mark Wancket retired from ISBE on December 31, 2011, with 32 years of service. Around January 2009, Wancket tendered an irrevocable notice of intent to retire in three years, effective December 31, 2011. By tendering his notice, Wancket triggered the accelerated compensation plan provision of his employment contract (negotiated through collective bargaining between Local 3236 of the Illinois Federation of State Office Educators (IFSOE) and ISBE). Under the accelerated compensation provision, Wancket liquidated 75 of his accumulated, unused 4 No. 1-23-2256 vacation days and 58.6 of his accumulated unused sick days, amounting to around a $1,250 increase to his monthly salary. Because SERS determines annuity payments based on the employee’s final average compensation, this bump to Wancket’s monthly compensation resulted in an estimated $80,000 in benefits overpayments to Wancket over the course of a decade. ¶ 13 In late 2021, SERS discovered that ISBE had been reporting payments for accumulated unused vacation days and sick days as “base pay” on certain employees’ payroll reports to the State Comptroller and SERS. ISBE explained to SERS that this adjustment was related to the “vacation liquidation agreement” (a.k.a., the accelerated compensation provision) that employees may exercise under the collective bargaining agreement. 1 SERS maintained that this practice improperly reported employee compensation, resulting in SERS overcalculating pension benefits for certain retirees. ¶ 14 SERS subsequently identified retired ISBE employees whose pensions had been increased as a consequence of the vacation liquidation agreements and issued letters explaining that their pensions annuities would be recalculated to exclude sick and vacation leave payments from the calculation of their compensation. Thus, each of those retirees was advised that their retirement annuities would be reduced. In cases where the error was discovered within three years, ISBE directed the retirees to repay the annuity overpayments. 1 Independent of the pension consequences, petitioners suggest that the accelerated compensation plan provides both the employer and employees benefits. The employees get to liquidate their benefits earlier, and for ISBE, the provision incentives higher-paid senior employees to retire. The irrevocable retirement notices are also useful to ISBE in making staffing and hiring decisions. Nonetheless, the retirees claim that they reasonably believed (and relied on their belief) that the accelerated payments would increase their pensionable compensation. 5 No. 1-23-2256 ¶ 15 SERS also realized that it had erroneously withheld pension contributions from the vacation and sick day payments as a result of how ISBE had reported the compensation. The letters explained to the retirees that improperly withheld contributions would be refunded. For Wancket, around $1,800 in additional pension contributions had been withheld. ¶ 16 Wancket sought to challenge the agency’s reduction of his pension. The agency held a hearing, and a hearing officer ultimately recommended that the Board deny Wancket’s challenge. In August of 2022, the Executive Committee of SERS’s Board of Trustees (the “Committee”) adopted the officer’s recommendation, finding that the statutory exclusion of “lump sum salary payments” entailed the payment of unused vacation and sick days in installments. The Committee found that it was “the policy of SERS to treat any payment that represents the cashing out of an unused vacation day or sick day as a lump sum salary payment excluded from pensionable compensation” and that it was consistent with this policy and the statute to treat installment payments as “lump sum salary payments” excluded from the calculation of final average compensation. The Committee analogized to Illinois family law cases where alimony in gross (i.e., a lump sum payment made in lieu of periodic alimony) was paid in installments. Thus, the Committee concluded, installment payments are compatible with the definition of “lump sum” where the installments are paid towards a definite sum. The Committee also bolstered their decision by citing numerous cases from other jurisdictions where vacation days and unused sick time were held to be excluded from pension or benefits calculation under their respective statutory schemes. ¶ 17 Wancket appealed to the full Board of Trustees, filing a brief and exceptions to the Committee’s decision. At its October 25, 2022, hearing, the Board voted to ratify the decision of the Committee over Wancket’s objections. On October 27, 2022, the Board issued a final 6 No. 1-23-2256 administrative decision denying Wancket’s administrative appeal. On the same day, the Board issued substantially similar final administrative decisions to the other petitioners. ¶ 18 On November 29, 2022, Wancket and the other petitioners brought an administrative review action to challenge the Board’s decisions. On November 3, 2025, after receiving briefing and hearing oral argument, the circuit court denied plaintiffs’ motion for summary judgment and affirmed the Board’s administrative decision. The court issued an oral decision in which it explained that the Board’s interpretation of “lump sum salary payments” could refer to multiple installment payments of the sum total owed for the unused vacation and sick days. The court also held that plaintiffs’ interpretation was unreasonable and in conflict with the legislature’s clear purpose in enacting the statute: “to prevent artificially inflating an employee’s pension by *** using [an employee’s unused vacation and sick leave] to calculate a pension” or, more briefly, “to remedy the issue of pension spiking.” ¶ 19 Two days later, petitioners filed this appeal. ¶ 20 III. ANALYSIS ¶ 21 Under the Pension Code, “lump sum salary payments *** for vacation *** [and] for accumulated unused sick leave” are excluded from compensation when calculating the “final average compensation” to determine retirement annuities. See id. §§ 14-103.10(b), 14-103.12. Between the parties, there is no dispute that a single payout for unused vacation and sick days, upon the retirement of an employee, would not be included in that employee’s final average compensation calculation. But the parties dispute whether payments for unused sick and vacation days, structured in multiple payments, would be excluded from the final average compensation calculation. 7 No. 1-23-2256 ¶ 22 In the case at hand, ISBE paid out for unused sick and vacation days to certain employees in semi-monthly payroll. Pursuant to a provision in the collective bargaining agreement between ISBE and its employees (originally negotiated in the 1999 to 2001 collective bargaining agreement and updated in later agreements), employees may elect to enter into a vacation liquidation agreement. Under this provision, the retiring employee would submit an irrevocable notice of intent to retire in 24 or 36 months, and, in exchange, the employee would receive payments for unused, accrued vacation and sick leave in bimonthly salary paychecks over the final two or three years of employment rather than in a singular payment upon retirement. ¶ 23 This appeal therefore requires us to decide whether paying accumulated unused vacation and sick leave through regular payroll installments makes those payments pensionable compensation or whether they remain excluded “lump sum salary payments.” ¶ 24 A. Standard ¶ 25 Decisions of the Board are reviewable under the Administrative Review Law (735 ILCS 5/3-101 etc. (West 2022)). 40 ILCS 5/14-150 (West 2022). On appeals of the circuit court’s decision on a complaint for administrative review, we review the administrative decision rather than the circuit court’s decision. Esquivel v. Retirement Board of the Policemen’s Annuity & Benefit Fund of Chicago, 2011 IL App (1st) 111010, ¶ 18. On review, we may affirm on any basis in the record. Wortham v. Village of Barrington Hills, 2022 IL App (1st) 210888, ¶ 25. The applicable standard of review depends upon “ ‘whether the question presented is one of fact, one of law, or a mixed question of fact and law.’ ” Cinkus v. Village of Stickney Municipal Officers Electoral Board, 228 Ill. 2d 200, 210 (2008) (quoting American Federation of State, 8 No. 1-23-2256 County & Municipal Employees, Council 31 v. Illinois State Labor Relations Board, State Panel, 216 Ill. 2d 569, 577 (2005)). ¶ 26 This litigation turns solely on an issue of statutory interpretation. The facts are not in dispute. We are asked to review only the Board’s interpretation of section 14-103.10 of the Pension Code. “[A]n agency’s interpretation of the meaning of the language of a statute constitutes a pure question of law.” Id. Statutory construction is a question of law that is considered de novo on review. Roselle Police Pension Board v. Village of Roselle, 232 Ill. 2d 546, 552 (2009). ¶ 27 When interpreting a statute, the court’s primary goal is to ascertain and give effect to the legislature’s intent. Id. The most reliable indicator of legislative intent is the statutory language itself, given its plain and ordinary meaning. Id. When the statute does not define a particular word or phrase, “it is entirely appropriate to look to the dictionary to ascertain the plain and ordinary meaning of the term.” People v. Chapman, 2012 IL 111896, ¶ 24. “Each word, clause, and sentence of a statute must be given a reasonable meaning, if possible, and should not be rendered superfluous.” Chicago Teachers Union, Local No. 1 v. Board of Education of Chicago, 2012 IL 112566, ¶ 15. Our supreme court has advised against “dissecting an individual word or phrase from a statutory provision and mechanically applying to it a dictionary definition” when determining legislative intent. Corbett v. County of Lake, 2017 IL 121536, ¶ 28. ¶ 28 “Where the language is clear and unambiguous, we must apply the statute without resort to further aids of statutory construction.” Krohe v. City of Bloomington, 204 Ill. 2d 392, 395 (2003). A statute is ambiguous where its construction is susceptible to “two equally reasonable and conflicting interpretations.” Land v. Board of Education of Chicago, 202 Ill. 2d 414, 426 9 No. 1-23-2256 (2002); see also Krohe, 204 Ill. 2d at 395-96 (“A statute is ambiguous if it is capable of being understood by reasonably well-informed persons in two or more different ways.”). ¶ 29 The interpretation of a statute by an agency that is charged with administering the statute is afforded “substantial weight and deference.” Stillo v. State Retirement Systems, 305 Ill. App. 3d 1003, 1007 (1999) (citing Abrahamson v. Illinois Department of Professional Regulation, 153 Ill. 2d 76, 88 (1992)). ¶ 30 Where there is a question as to the legislative intent and clarity of the language of a pension statute, the statute must be “liberally construed in favor of the rights of the pensioner.” Prazen v. Shoop, 2013 IL 115035, ¶ 39; Carmichael v. Laborers’ & Retirement Board Employees’ Annuity & Benefit Fund of Chicago, 2018 IL 122793, ¶ 50 (where pension statute found to be ambiguous, courts must apply liberal construction in favor of the pensioner). ¶ 31 In addition to the plain text, “the court may consider the reason for the law, the problems sought to be remedied, the purposes to be achieved, and the consequences of construing the statute one way or another.” Sigcho-Lopez v. Illinois State Board of Elections, 2022 IL 127253, ¶ 28. In construing a statute, we must presume that the legislature did not intend an absurd result. Carmichael, 2018 IL 122793, ¶ 45 (citing People v. Fort, 2017 IL 118966, ¶ 35). ¶ 32 B. “Lump Sum” ¶ 33 The phrase “lump sum” in section 14-103.10(b) (40 ILCS 5/14-103.10(b) (West 2022)) is not defined by the Pension Code, and no Illinois court has interpreted its meaning in this provision. The proper construction of “lump sum” is thus a matter of first impression in Illinois. ¶ 34 1. Petitioners’ Interpretation ¶ 35 Petitioners’ interpretation of the Pension Code is based upon a strict interpretation of the phrase “lump sum.” According to petitioners, the plain text of the Pension Code provides that 10 No. 1-23-2256 one-time salary payments (i.e., payments by “lump sum”) within the enumerated categories are excluded from pension calculations. Multiple payments, including installments made for enumerated items (e.g., unused vacation time), are argued to fall outside of the definition of “lump sum” and, hence, are not excluded under the Code. ¶ 36 Read in a vacuum, petitioners’ interpretation of the isolated phrase “lump sum” is consistent with how several dictionaries define the term. Black’s Law Dictionary defines “lump sum” as “A single payment made once, usu. at a particular time, as opposed to a series of smaller payments.” Sum, Black’s Law Dictionary (12th ed. 2024). The phrase “lump-sum payment” shares a similar definition, meaning “[a] payment of a large amount all at once, as opposed to a series of smaller payments over time.” Payment, Black’s Law Dictionary (12th ed. 2024). The Merriam-Webster Online Dictionary defines “lump sum” as “an amount of money that is paid at one time : a single sum of money.” Merriam-Webster Online Dictionary, https://www.merriam-webster.com/dictionary/lump%20sum (last visited Sept. 23, 2026) [http://perma.cc/8EA7-DL2Q]. The American Heritage Dictionary defines “lump” as “[n]ot broken or divided into parts” as in “one lump payment.” (Emphasis in original.) American Heritage Dictionary 746 (2d coll. ed. 1985). And it defines “sum” as “[2] [t]he whole amount, quantity, or number; aggregate *** [3] An amount of money.” Id. at 1218. ¶ 37 Each cited definition specifically contradistinguishes lump sum payments from installments or smaller, periodic payments. Petitioners argue that these dictionary definitions support a plain text reading of the statute that limits the exclusion to one-time, complete payments for unused vacation and sick time. ¶ 38 For petitioners, this definition effectively ends the analysis. If this restrictive interpretation of “lump sum” modifies “payments,” then anything other than a single payment per category 11 No. 1-23-2256 falls outside the exclusion. Although petitioners’ reading has some support in the dictionary definitions, we do not find it reasonable when the phrase is read in the context of the statute as a whole. ¶ 39 While arguing that the provision does not implicate the legislature’s interest in preventing “pension spiking,” petitioners argue that the legislature was concerned with something approximating it. According to petitioners, “[t]here is a straightforward, rational reason why the legislature would have limited the compensation exclusion to single, lump sum payments *** [L]arge, one-time payments would have the most unpredictable impact on the actuarial assumptions of the pension system.” Despite insisting upon this legislative purpose, petitioners struggle to justify why the legislature drew the line where it did. Ironically, by attempting to tie their reading of the statute to this legislative intent, petitioners only demonstrate how severely underinclusive the exclusion would be under their reading. According to petitioners, the legislature was concerned with large, singular payments, but apparently was not concerned if the same payment was split into two or more payments, even if the ultimate effect was the same. ¶ 40 When challenged on this point, petitioners embrace the arbitrariness, defending the underinclusiveness as legislative choice: “[L]ines drawn by the legislature tend to be arbitrary, as lines generally are, but that the government is in the business of drawing them.” See Alamo Rent A Car, Inc. v. Ryan, 268 Ill. App. 3d 268, 275 (1994). According to petitioners, the legislature had to draw a line somewhere in deciding what was included in or excluded from pensionable compensation, and we cannot second guess their policy decision where the statute is clear even if the line drawn appears to be inadequate for its legislative purpose. 12 No. 1-23-2256 ¶ 41 But there is no obvious reason why the legislature would have drawn the line at one payment. Even granting petitioners’ point that lawmaking entails the drawing of arbitrary lines, this line seems particularly arbitrary, and it obviously does not serve the legislature’s purpose in drafting the exclusion. ¶ 42 First, petitioners attempt to justify the legislature’s choice to limit the exclusion to one- time payments by suggesting they are more disruptive than two or more payments, but there is no foundation for the assertion that they are or that the legislature believed that they were. Petitioners attempt to rationalize the assumption in the context of this case where 72 payments were made over three years, suggesting that SERS had enough lead-up to account for these payments. But this is also dubious; no briefing is offered as to when or how these actuarial assumptions are made, nor how much lead time is necessary for the pension system to account for an inflation in employee pensionable compensation in their final three years. Petitioners’ narrow reading of the legislative intent is built upon an unfounded premise. ¶ 43 Second, the legislature need not have drawn a line here at all: in respondents’ interpretation, what matters is not the manner of payment, but the source of the payment. That petitioners’ interpretation requires that we make an exceedingly narrow assumption of legislative intent and accept the exclusion’s ineffectiveness as just a consequence of arbitrary legislative line- drawing is good reason to infer that the interpretation is simply not a reasonable or accurate construction. ¶ 44 Third, petitioners’ interpretation also places too much weight on how the payments are made and too little on what they are for. The statute does not exclude lump sum payments generally. It identifies four categories: vacation, accumulated unused sick leave, discharge or dismissal, and approved holidays. The specific identification of those categories supports 13 No. 1-23-2256 SERS’s view that the source of the payment matters. Spreading a payment for one of those categories over several categories does not change its source. ¶ 45 Petitioners’ ultimate recourse is to Carmichael, and the principle that pension statutes must be constructed in favor of the pensioner. To the extent that there is any “lingering doubt about the meaning or effect of the provisions *** we must resolve that doubt in favor of the members of this State’s public retirement system.” Carmichael, 2018 IL 122793, ¶ 24. Petitioners insist that, given the dictionary definitions of “lump sum,” their interpretation of the statute is reasonable. At the very least, the contextual meaning of the terms “lump sum” and “payments” are ambiguous, so even if the statute is susceptible to SERS’ construction, petitioners assert that Carmichael requires that we adopt the interpretation in favor of the pensioners. ¶ 46 But petitioners’ construction of “lump sum salary payments” is not reasonable when the provision is read as a whole. The statute therefore is not ambiguous, and the Carmichael presumption does not apply. ¶ 47 2. Respondent’s Interpretation ¶ 48 Respondent offers a counter-interpretation that the term “lump sum” entails installment payments against a definite amount. For respondent, the essential quality of a “lump sum” is that it corresponds to a known and definite amount of money owed, rather than the manner of payment. Under this interpretation, the value of unused, accumulated time is a discrete amount of money—a “lump sum”—owed to retirees distinct from their bimonthly salary (which is indeterminate and ongoing in comparison). Consequently, the method of payment is irrelevant; a lump sum may be paid all at once, or payments may be made against the lump sum owed. ¶ 49 SERS argues that the language of the clear legislative intent of the provision was to prevent “pension spiking.” “Pension spiking” describes the artificial inflation of a retiree’s pension 14 No. 1-23-2256 annuity that is effected by the disbursement of payments during the final average compensation reporting period (typically last few years of the retiree’s employment). A retiree’s pension annuity is calculated using their highest consecutive years of compensation. A pension can be “spiked” where payments that would otherwise be made outside of the reporting period are shifted into that period, creating the appearance of a higher average compensation. See Pisani v. City of Springfield, 2017 IL App (4th) 160417, ¶ 11 (“[R]egardless of what the lump sum is for, the objective is to make the final rate of earnings artificially large, so as to increase the amount of the annuity.”). “Because pension spiking *** ‘is likely one of the many causes of the serious underfunding problem *** in Illinois,’ the General Assembly has passed laws that are calculated to prevent pension spiking.” Id. ¶ 12 (quoting Illinois Municipal Retirement Fund Board). ¶ 50 The statutory scheme supports SERS’s interpretation. The provision excludes categories of payments from being treated as compensation for the purposes of pension calculations. The categories of payments excluded under section 14-103.10(b) are types of payments for benefits accumulated over time and typically paid out in a single sum on retirement or termination. Because these benefits are not paid out regularly, but instead accumulate over time, there is an inherent risk that employees and employers could shift payments into the final average compensation reporting period for work done from outside of that period—a classic form of pension spiking. The statute’s exclusion evinces a clear legislative intent to prevent that type of pension manipulation. ¶ 51 SERS’s interpretation is also consistent with a construction of the term “lump sum.” Under SERS’s interpretation, “lump sum” describes a fixed amount attributable to one of the listed categories; it does not require that the entire amount be paid at once. Payments for sick leave, 15 No. 1-23-2256 vacation time, holidays, or upon discharge or dismissal are typically for discrete amounts and are generally not made periodically. So, payments within these categories can reasonably be characterized as payments of lump sums. Moreover, the statute also contemplates that these payments might be made earlier. The statute lists “vacation” and “sick leave” payments alongside payments “upon discharge or dismissal,” suggesting that the legislature intended to exclude payments for the listed categories even if paid prior to termination. ¶ 52 That SERS treats accumulated unused sick leave and vacation time as non-pensionable “lump sum” is evident from their historical practice. In 2011 and 2016, SERS issued bulletins concerning payroll practices to various state agencies including ISBE. The 2011 payroll bulletin states that the enumerated categories under section 14-103.10(b) (40 ILCS 5/14- 103.10(b) (West 2022)) are “lump sum salary payments,” which are “EXCLUDED from any employee retirement contribution liability.” The 2016 bulletin accorded with this guidance, advising state agencies to process lump sum payouts of holiday time “using the lump sum fields within the payroll system.” After quoting the full list under section 14-103.10(b), the bulletin emphasized that “under no circumstances should they be paid as gross adjustments allowing retirement deductions to be taken and wages to be falsely accumulated.” ¶ 53 SERS’s guidance reflects its longstanding view that payments covered by the statutory exclusion should not be processed in a way that allows retirement deductions to be taken and pensionable wages to accumulate. Although not binding, the “interpretation of a statute by the agency charged with its administration is generally given deference” unless it is erroneous. Taddeo v. Board of Trustees of the Illinois Municipal Retirement Fund, 216 Ill. 2d 590, 595 (2005). 16 No. 1-23-2256 ¶ 54 We address, briefly, two additional arguments made by SERS in support of its interpretation. First, SERS attempts to found a construction of “lump sum” that entails installments by looking to family law cases. In a number of cases, courts refer to “ ‘lump sum property settlement[s]’ ” under which maintenance or alimony were payable in installments. See, e.g., Walters v. Walters, 409 Ill. 298, 299 (1951); Roberts v. Roberts, 90 Ill. App. 2d 184, 186 (1967); Koivun v. Koivun, 45 Ill. App. 3d 39, 41-42 (1977); In re Marriage of Hildebrand, 166 Ill. App. 3d 795, 799 (1988). The use of “lump sum” in these cases fits into a distinction between awards of alimony or spousal support in gross and periodical support. Alimony made “in gross” refers to a fixed monetary sum, whereas “periodic” alimony refers to alimony payments made periodically for an indefinite amount of time. See Koivun, 45 Ill. App. 3d at 41-42. Typically, alimony in gross defines the total amount owed for alimony as a single sum in a property settlement that is agreed to “in lieu of all alimony,” which, for the parties, has the added benefit of not being modifiable by a court (e.g., on the occasion of the supported spouse’s remarriage). Walters, 409 Ill. at 302-03. “Lump sum” settlements are therefore related to in gross alimony as distinguished from periodic alimony in these cases. ¶ 55 For our purposes, these cases offer little support. First, we note that the phrase “lump sum payments” is not found in any of the above cases. Instead, the phrase “lump sum” modifies “award” or “settlement agreement.” This follows from the aforementioned distinction between in gross and periodic alimony: the award of a lump sum maintenance obligation defines the obligation as a single, definite sum, in contradistinction to a periodic, indefinite maintenance obligation. See, e.g., Koivun, 45 Ill. App. 3d at 42 (“[D]efendant agreed to forego receiving periodic alimony for an indefinite period of time and agreed to a certain lump sum settlement paid in installments.”). 17 No. 1-23-2256 ¶ 56 First, as we discuss in the following section, we do find that it is consistent with the definitions of “lump sum” to describe a particular payment obligation as a “lump sum” that may be payable in installments. See Kroger Co. v. Blumenthal, 13 Ill. 2d 222, 224 (1958). ¶ 57 Second, SERS argues that its interpretation aligns with earlier versions of the statutory provision and that we ought to consider the history of amendments to the Pension Code to determine the legislative intent. Prior to the 1978 amendment, the Pension Code defined compensation as “[s]alary or wages payable on a regular payroll *** to any person for personal services currently performed.” Ill. Rev. Stat. 1975, ch. 108½, ¶ 14-113 (amended and renumbered 1978). The limited discussion available regarding the amendment suggests that the legislature amended the Pension Code as to revise the definition of “final average compensation to parallel the Social Security Act definition.” 80th Ill. Gen. Assem., Senate Proceedings, June 24, 1977, at 208 (statements of Senator Egan). SERS emphasizes that the amendment was introduced as a “housekeeping, clean up type bill” (id.), to argue that