Opinion for the Court filed by Circuit Judge BROWN.
A grоup of former employees (class members or Aliotta plaintiffs) of the Federal Deposit Insurance Corporation (FDIC or the Agency) sued the Agency, alleging violation of the Age Discrimination in Employment Act (ADEA), 29 U.S.C. § 633a. 1 Specifically, class members claimed FDIC’s management targeted older employees in a series of downsizings implemented between 1998 and 2005. The district court granted summary judgment on all claims in FDIC’s favor, determining— after excluding the employees who accepted FDIC’s buyout/early retirement offer from its statistical analysis — that the class members failed to produce evidence from which a jury could reasonably conclude that (1) FDIC intentionally treated older employees less favorably than younger employees, or (2) that a neutral employment practice fell more harshly on older employees and could not bе justified by business necessity. We agree and affirm the judgment of the district court.
I
The FDIC is an independent federal agency that insures federal bank and savings and loan deposits. It also regulates state-chartered banks, establishes receiverships, and manages assets of failed banking institutions. FDIC’s workload—
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especially the workload of the Division of Resolutions and Receiverships (DRR) — is highly correlated with the health of the banking industry: when bank failures increase, FDIC’s workload increases; when bank failures decrease, FDIC’s workload declines.
See Aliotta v. Bair,
On August 6, 2004, FDIC Chief Operating Officer John Bovenzi sent an e-mail to all FDIC employees entitled “Workforce Planning for the Future.” The memo outlined certain “preliminary conclusions” related to the “2005 planning and budget formulation process,” evaluating industry and technological trends, forecasting the need for greater agility and adaptability by thе agency, and stated: “The FDIC of the future will be a smaller, more flexible agency.” Bovenzi explained that “all indicators point[ed] to a smaller FDIC with a somewhat different mix of skills in the future” and warned that some divisions and offices within the Agency might reduce overall staffing levels, while others might have “workload requirements or skill set[ ] imbalances that warrant filling selected vacancies.” Two weeks later, DRR Director Mitchell Glassman sent a follow-up memo to his division’s employees confirming the Agency’s view that changes in the banking industry, advances in technology, and workflow improvements had led to “declining workload and excess staff’ and thus might require “difficult decisions ... regarding the size and structure of [the] division.” This communication was followed by a string of e-mails and memos implementing cross-training plans, voluntary rotational assignments, and other staffing changes, forecasting staff reductions оf 500 to 600 positions, and predicting that an involuntary Reduction-in-Force (RIF) 2 would still be required.
In a series of memos in October 2004, FDIC management informed staff it planned to reduce the DRR workforce by 53%, from 515 to 240 positions. Buyouts would be offered to all permanent DRR employees (with the exception of a small group of “Executive Management” employees), as well as to employees throughout the Agency on a more limited basis. The offer would include a cash payment equal to 50% of the employee’s total annual salary, the ability to combine the buyout with regular or early retirement, and no restrictions on the employee’s ability to seek employment in another federal agency. The buyout period would last from November 2004 to May 2, 2005. Director Glassman’s memo also informed DRR employees they would have the opportunity to apply for crossover opportunities with the Division of Supervision and Consumer Protection (DSC) through the Agency’s Corporate Employee Program (CEP). Lastly, Glassman explained that a RIF would be implemented during 2005 “to involuntarily separate any remaining surplus [DRR] employees.”
More than 575 FDIC employees applied for and accepted the buyout. 132 were DRR employees. Another 73 DRR employees transferred to other FDIC divisions. Moreover, as planned, in April 2005, Glassman announced the RIF would go forward and would be effective September 3, 2005. Glassman informed DRR employees that, “while the outcome of the RIF [was] not known, [his] notice [was] intended to alert [them] to the possibility [they] could be impacted through the RIF process.” As of June 30, 2005, 312 permanent DRR employees were subject to the RIF. 56.1% of them were over age 50. Those employees who had resigned or retired before June 2005 in connection with *560 the buyout program were not considered in the RIF process. 63 DRR employees were selected for involuntary termination and received RIF Notices terminating their employment, effective September 3, 2005. 3 FDIC terminated 53 of those 63 employees; 7 retired in lieu of separation; and 3 voluntarily resigned after receiving a specific RIF Notice. 233 DRR employees remained after the RIF.
In fall and winter 2005-06, the employees filed notices with the Equal Employment Opportunity Commission (EEOC). Am. Compl. ¶ 4,
Aliotta v. Gruenberg,
No. 05-02325 (D.D.C. Feb. 8, 2006) (Am. Compl.);
see
29 U.S.C. § 633a(d). On December 5, 2005, they filed their complaint in the district court alleging FDIC violated 29 U.S.C. § 633a, the portion of the ADEA applicable to federal employers.
See
29 U.S.C. § 633a(c). On July 25, 2006, the district court granted the employees’ motion for class certification, defining the class as “[fjormer or present employees of FDIC’s Division of Resolution and Receivershiрs who were born on a date on or before September 30, 1955 and who, as a result of the 2005 RIF, either accepted a buyout or reduction in grade, or were terminated from their positions in the DRR.”
Aliotta v. Gruenberg,
The parties filed cross-motions for summary judgment in the district court and submitted expert reports providing statistical analyses to support their positions. Analyzing only the 53 involuntary separations, 7 retirements in lieu of involuntary separation, and 3 resignations in lieu of involuntary separation, FDIC’s expert, industrial and organizational psychologist Dr. P.R. Jeanneret, found the average age of the 63 DRR employees affected by the 2005 RIF was 48.28 years. Def.’s Mot. Summ. J., Ex. 27 at 6 (Jeanneret Report). Only 42.9% of the RIF’d employees were above the age of 50. Def.’s Mot. Summ. J., Ex. 27-1 at 20 (filed Feb. 26, 2008) (Jeanneret Rebuttal). On December 31, 2004 (before the RIF), 59.1% of permanent DRR employees were above the age of 50; on September 17, 2005 (after the RIF), the percentage of above-50 employees had increased slightly to 59.6%. Jeanneret Report at 17.
In contradistinction to Dr. Jeanneret’s statistical analysis, class members’ expert, Dr. Lance Seberhagen, included in his calculation of the “RIF-related” impact all employees affected by both the 2004-05 buyouts and the 2005 RIF. Def.’s Mot. Summ. J., Ex. 28 (Seberhagen Report). Dr. Seberhagen identified a set of “RIF-related separation codes” he believed captured the group of employees harmed. Id. at 3. The group included the codes assigned to voluntary retirements, early retirements, retirements and resignations in lieu of involuntary separation, resignations, terminations of term appointments, and involuntary terminations. Id. at 3, 17 tbl.20. Using those codes, he found that permanent DRR employees above the age of 50 were sеparated at 139.8% the rate of under-50 DRR employees. Id. at 5.
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Rejecting Dr. Seberhagen’s analysis, the district court granted FDIC’s motion for summary judgment and denied class members’ motion for partial summary judgment.
Aliotta,
II
Before proceeding to the merits, we first address FDIC’s assertion class members waived their right to challenge the district court’s failure to analyze their claims under the appropriate “pattern or practice” framework. FDIC insists class members never claimed before the district court FDIC engaged in a pattern or practice of discrimination. FDIC Br. at 22. We con-elude class members alleged a pattern or practice claim in their complaint but may nonetheless have failed to preserve it at the summary judgment stage. However, even assuming they did preserve their pattern or practice claim, summary judgment was properly granted because the vagaries of the various analytical frameworks were no longer relevant.
Plaintiffs alleging age discrimination in violation of the ADEA may seek recovery under both disparate treatment and disparate impact theories of rеcovery.
See Smith v. City of Jackson,
A. Class Members’ Disparate Treatment Claim
Disparate treatment claims brought under the ADEA may involve “an isolated incident of discrimination against a single individual, or ... allegations of a ‘pаttern or practice’ of discrimination affecting an entire class of individuals.”
Palmer v. Shultz,
In their amended complaint, the Aliotta plaintiffs alleged a persistent pattern or practice of discrimination spanning almost a decade.
See
Am. Compl. ¶¶ 56-94. The recitation included allegations that remarks made by FDIC management were hostile to older emрloyees as well as allegations that buyout offers and RIFs in 2002, 2003, and 2004 were specifically designed to reduce the number of older employees and that the complete sequence of events showed discrimination against employees over the age of 50 was the “regular rather than the unusual” practice at FDIC.
Teamsters,
In their motion for partial summary judgment, class members focus only on the 2004-05 buyout and point to no policies or other employment decisions targeting or adversely affecting older employees.
See
Pis.’ Summ. J. Mem. at 1-4,
Aliotta v. Bair,
No. 05-02325 (D.D.C. Feb.25, 2008). Nor do they argue there is a material dispute concerning an intentional pattern or practice of discrimination. More significantly, FDIC challenged the disparate treatment claim and argued it should be analyzed under the
McDonnell Douglas
framework applicable to individual discrimination claims, not the
Teamsters
framework, and class members’ opposition did not dispute the Agency’s position.
See
Def.’s Mot. Summ. J. at 22; Pis.’ Opp’n. at 29 (citing
Teamsters
only оnce and for a general proposition applicable to both individual and pattern or practice claims);
see, e.g., Muhammad v. Giant Food Inc.,
The forfeiture debate seems largely beside the point. The class members’ singular focus on the
Teamsters
analysis appears to hinge on a distinction without a difference. Once a prima facie case is established, the burden shifts to the employer to rebut the inference of discrimination by showing the employees’ proof is either inaccurate or insignificant.
Teamsters,
Under our decision in
Brady v. Office of Sergeant at Arms,
Nonetheless, while
Brady
held that in an
individual
discrimination case, an employer’s mere assertion of a legitimate, nondiscriminatory explanation renders the question whether the plaintiff made out a prima facie case “almost always irrelevant,”
id.
at 493, our decision in
Segar v. Smith
requires more from an employer in a pattern or practice case.
See Segar,
In Segar, the court concluded the rebuttal of the employer, the federal Drug Enforcement Agency (DEA), failed as a matter of law because DEA submitted no admissible evidence to support its purported nondiscriminatory explanation. Id. at 1287-88. Here, FDIC sought to rebut class members’ prima facie case in two ways. First, the Agency offered a legitimate, nondiscriminatory explanation for the RIF: it implemented the RIF to respond to decreased workload in DRR due to the improved health of the banking industry and to improve the Agency’s responsiveness and efficiency. See Def.’s Mot. Summ. J. at 28. Unlike the employer in Segar, who presented no admissible evidence supporting its nondiscriminatory justification, FDIC submitted numerous communications between Agency officials and employees explaining its nondiscriminatory reasons for the RIF. See, e.g., Email from DRR Director Mitchell Glass-man to DRR Employees (Aug. 19, 2004) (stating “[r]ecord profitability and capital in the banking industry,” “[i]ndustry consolidation,” “[e]merging technology,” and “improved business processes” had led to
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“a declining workload and excess staff’ and would require some “difficult decisions” regarding the “size and structure” of DRR); E-mail from FDIC Chief Operating Officer John Bovenzi to FDIC Employees (Oct. 26, 2004) (explaining a RIF in certain divisions would likely be necessary since “staffing levels [were] not justified by current or projected workloads”). Class members did not, at the summary judgment stage, and have not, on appeal, pointed to any evidence refuting FDIC’s claim the RIF targeted DRR because of the division’s reduced workload caused by improved conditions in the banking industry.
See Aliotta,
FDIC’s rebuttal also included an attack on class members’ statistical methodology. FDIC argued the buyout employees should not be included in class members’ disparate impact analysis and submitted reports from its own statistical expert refuting their methodology,
see
Jeanneret Report at 6, 24; Jeanneret Rebuttal at 9-11. Unlike DEA’s attack on the plaintiffs’ statistical proof in
Segar,
FDIC satisfied its rebuttal burden, and class members’ prima facie case is therefore irrelevant. In order for class members to succeed on their disparate treatment claims, they must have produced evidence sufficient to demonstrate FDIC’s nondiscriminatory reason for the RIF was pretext and that FDIC intentionally discriminated against older workers.
See Brady,
B. Class Members’ Disparate Impact Claim
Class members’ disparate impact claim is easier to parse. In
Segar,
we held a class of plaintiffs alleging a pattern or practice of discrimination may also challenge the disparate impact of specific employment practices.
Segar,
In their amended complaint, class members allege the 2005 RIF “had a discriminatory impact against plaintiffs and other employees over the age of 50.” Am. Compl. ¶ 86. At the summary judgment stage, they again argued FDIC’s actions disparately affected older employees and
*566
offered statistical evidence to support their claim.
See
Pis.’ Opp’n at 9-13. The district court, however, concluded class members’ statistics were invalid and established no disparate impact.
Aliotta,
Ill
The foregoing analysis reveals class members may not have preserved a distinct pattern and practice claim, but they assert both disparate treatment and disparate impact. Both class member claims are premised almost entirely upon the statistical findings of their expert, Dr. Seberhagen. In order for class members to show a disparate effect on older workers, they must combine the effects of the involuntary terminations resulting from the 2005 RIF with the effects of the voluntary retirements from the 2004-05 buyout offers. But, as the district court properly concluded, id. at 120-24, class members cannot include as evidence of discrimination the statistics of a group of employees who, because they voluntarily accepted a buyout, suffered no adverse employment action. Without the inclusion of the voluntary terminations, class members’ claims of discrimination collapse. The statistical impact of the involuntary RIF terminations reveals a disparate effect on younger, not older, employees, see Jeanneret Rebuttal at 14-16, 19-20 tbls.2, 3 & 4.
Under either a disparate treatment or disparate impact theory of discrimination, plaintiffs must show they suffered an adverse employment action.
See, e.g., Barnette v. Chertoff,
“ ‘[Resignations or retirements are presumed to be voluntary....’”
Veitch v. England,
Class members argue the district court could not consider the voluntariness of the buyouts — an individual question — until the remedial phase of their pattern and practice claim and that even if the question of voluntariness could be addressed during the liability phase, the court resolved it incorrectly. The former argument is specious; the district court considered voluntariness not in determining the remedial issue whether any individual employee was entitled to compensation, but rather in determining whether the statistical analysis proffered by the class members showing a disparate number of older employees accepted the buyout could “comprise any part of [their] prima facie case of discrimination.”
Aliotta,
That leaves the question of whether FDIC’s buyout offers were voluntary. Class members argue they wеre not and thus constitute an “adverse employment action” on which they premise liability under the ADEA. Employees’ Br. at 15-17, 53-59. Accordingly, they contend any analysis of the sufficiency of their proof should include those employees who accepted the buyout. Id. at 35-38. After reviewing the Agency’s reorganization charts and seniority lists, class members say many older DRR employees were convinced they faced a “near certainty of being terminated in a RIF” if they did not accept the buyout. Id. at 17. Because the employees “reasonably believed they were going to lose their jobs” if they did not accept early retirement, they were essentially “compelled” to accept the buyout. Id. at 15, 57-58. The employees’ decisions to accept the buyout, class members argue, were motivated not by the attractiveness of the offer, but rather by the “terror of the alternative.” Id. at 17. We are not persuaded.
Undoubtedly, the employees who accepted buyout offers faced a difficult decision: they could leave the Agency early and receive an incentive payment and benefits, or they could choose to stay and face the risk of termination in the RIF. But, senior employees were not faced with “an impermissible take-it-or-leave-it choice between retirement or discharge,”
see Rowell,
First, with the possible exception of a few individual employees who claim the size
of the
reduction and the veterans and seniority preferences of their co-workers guaranteed they would not survive a RIF,
see
Employees’ Br. at 15-16, employees considering whether to accept the buyout
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could do no more than speculate that they might be terminated. Although a RIF seemed inevitable, see E-mail from FDIC COO John Bovenzi to FDIC Emрloyees (Oct. 26, 2004) (indicating the “necessary staffing reductions [in DRR] ... c[ould not] be accomplished entirely through voluntary departures”) (Bovenzi E-mail), it was impossible for DRR employees to know
how many
employees would be subject to the RIF. That number was dependent on retirements, transfers to other divisions within the Agency, and general attrition. Moreover, it was impossible for employees deciding whether to leave voluntarily to know exactly who would be RIF’d. As noted
supra,
FDIC’s RIF process gives preference to certain types of employees — for example, veterans and those with seniority. Without knowing whether certain employees with those preferences would be subject to the RIF, it was impossible for employees to calculate their chances of surviving the RIF — a chance that improved if a greater number of preference employees accepted the buyout and dropped out of the competition for positions. Moreover, the “bump” and “retreat” rights of FDIC employees subject to a RIF are complex,
see
5 C.F.R. § 351.701;
Aliotta v. Bair,
Decl. of Pamela K. Mergen, Lead Human Resources Specialist at FDIC, No. 05-cv-02325 (D.D.C. Feb. 21, 2008);
see also Benjamin Franklin Am. Legion Post No. 66 v. U.S. Postal Serv.,
Furthermore, employees were not pressured into accepting the offer.
Cf. James v. Sears, Roebuck & Co.,
The district court’s rejection of class members’ statistics also implies, as suggested by FDIC in the record, that the statistics were based on a flawed methodology and therefore not probative of whether the Agency intentionally discriminated against older employees. As demonstrated by our discussion above, there are multiple reasons an older employee presented with a buyout offer of early retirement in advance of an impending RIF might choose to accept the offer. The employee might feel she has no choice because being involuntarily terminated in the RIF is inevitable. Alternatively, the employee may simply believe the early retirement offer is such a good deal she voluntarily chooses to take advantage of the buyout incentives. Dr. Seberhagen’s statistics, however, do not appear to consider employee choice. If his statistics do not control for this important explanatory variable, they tell us nothing about
why
older employees took the buyouts, and are therefore not relevant to determining whether FDIC disсriminated against them.
See, e.g., Garcia v. Johanns,
Class members also argue our decision in
Schmid v. Frosch,
Class members construe our holding in
Schmid
far too broadly. In
Schmid,
we concluded the group of employees actually “hurt” by the RIF and thus “probative” of the plaintiffs age discrimination claim were those who had received RIF notices and were either separated or downgraded as a result.
Accepting an employer’s offer of voluntary early retirement may often be beneficial to older or more senior employees.
See Henn,
IV
Having concluded FDIC’s voluntary buyouts were not adverse employment actions and thus should not be considered as part of class members’ case, we analyze only the independent effect of the 2005 RIF itself and find that, once the buyouts are excluded, their case effectively collapses. The remaining statistical evidence supports neither of their claims.
The average age of those employees separated by the RIF was 48.28 years. Jean *570 neret Report at 6. 62% of the RIF’d employees were under age 50. Jeanneret Rebuttal at 13. Moreover, the RIF’d population was statistically significantly younger than the population from which it was drawn. While 56.1% of permanent DRR employees subject to the RIF were over 50, only 42.9% of those actually RIF’d were 50 or older. Id. at 14. Between December 2004 (before the RIF) and December 2005 (after the RIF), the average age of DRR employees remained constant at 52.10 years of age. Id. at 12; Jeanneret Report at 16 ex.4, and the average age of the overall FDIC workforce increased slightly from 46.63 years to 46.93. Defs.’ Mot. Summ. J., Ex. 23 at 27 tbl.F. Thus, the relevant statistics do not support the employees’ theory that the RIF disproportionately affected older employees. If anything, the evidence establishes exactly the opposite — that the RIF disproportionately affected younger employees.
V
In addition to their flawed statistical analysis, class members argue certain statements made by FDIC officials raise a reasonable inference of discriminatory bias against older employees. They assert then-Chairman Donald Powell’s comment made in 2001 or 2002 to a group of employees that he “want[ed] young people around [him] ... [because] they have all the innovative ideas” and a statement made by the then-Deputy Chairman of the FDIC, Donald Greer, in a 1995 magazine article that he would like to “keep some of the youngest and brightest people who are moving up in the ranks” support the inference that FDIC targeted DRR for reduction in 2004-05 because it had the highest proportion of older employees among the Agency’s divisions. Employees’ Br. at 47-50. The district court dismissed Chairman Powell’s statements as unsupportive of class members’ claims because they did not present any evidence Pоwell actually made the alleged statement.
Aliotta,
Lastly, class members contend FDIC’s Corporate Employee Program demonstrates FDIC’s 2004-05 downsizing efforts were not intended to respond to a reduced workload but rather to purge the Agency of older DRR employees and replace them with younger ones. Employees’ Br. at 43-46. The district court rejected class members’ theory, concluding that because the positions created under the CEP were for workers assuming different responsibilities in different departments than the employees, the two groups were “not so similarly situated as to support the proposition that the FDIC conducted the voluntary buyout, transfers and RIF as an elaborate ruse to flush the agency of senior staff.”
Aliotta,
VI
For the foregoing reasons, the judgment of the district court is
Affirmed.
Notes
. Section 633a requires that "[a]ll personnel actions affecting employees or applicants for employment who are at least 40 years of age ... in executive agencies ... shall be made free from any discrimination based on age.” 29 U.S.C. § 633a(a).
. A "reduclion-in-force” is an administrative procedure that allows agencies to eliminate jobs and reassign or terminate employees who occupied the abolished positions.
. Reductions-in-Force are governed by 5 C.F.R. pt. 351 and FDIC’s RIF Circular 2100.4. See FDIC Br. at 11. The process requires two rounds of competition and provides employees who might otherwise be terminated with certain "bump” and "retreat” rights. See 5 C.F.R. § 351.701. The process favors veterans, as well as employees with seniority and job experience within the agency. See id. §§ 351.501-504. FDIC is also required to notify employees likely to be affected once a decision is made to conduct a RIF and must send specific RIF notices to employees selectеd for a RIF action. See id. § 351.801(a)(1); Def.’s Mot. Summ. J., Ex. 21, Aliotta v. Bair, No. 05-02325 (D.D.C. Feb.25, 2008) (Def.'s Mot. Summ. J.). The employees do not allege FDIC did not conduct its 2005 RIF in accordance with federal regulations or its own Agency guidelines.
. Although neither this court nor the Supreme Court has addressed the question whether the ADEA authorizes disparate impact claims against
federal
employers, we need not resolve the issue in this case since we conclude class members have failed to demonstrate any adverse effect on older employees.
See City of Jackson,
. In
Teamsters,
the plaintiffs brought their “pattern or practice” discrimination claims under Title VII of the Civil Rights Act of 1964.
. The district court did not discuss the then-Deputy Chairman's alleged statement, but even if class members provided sufficient evidence he actually made the statement, it is insufficient, on its own, to establish proof of discriminatory intent.
See, e.g., Bevan v. Honeywell,
