OPINION OF THE COURT
A. LEON HIGGINBOTHAM, Jr., Circuit Judge.
The International Union of Wholesale and Department Store Union, AFL-CIO (the International) appeals for a second time from an order of the district court which holds it liable in contribution to The G. C. Murphy Company (Murphy) for violations of Title VII of the Civil Rights Act of 1964, as amended, 42 U.S.C. §§ 2000e-2000e-17 (Title VII). Murphy cross-appeals challenging the district court’s calculations of the International’s liability. We agree with the district court that Murphy has a right of contribution. We will affirm.
I.
These appeals arise out of a class action brought in 1971 on behalf of all females employed by The G. C. Murphy Company from July 1965 to January 1971. The plaintiffs in that action named as defendants Murphy; the International; the Retail, Wholesale and Department Store Union, Local 940 (Local 940); and Teamster’s Local 249 (Local 249), the successor collective-bargaining agent of Local 940. They alleged, inter alia, that Murphy and the unions had violated Title VII and the Equal Pay Act of 1963, 29 U.S.C. § 206, by agreeing to and maintaining a collective-bargaining agreement that provided for separate job classifications, pay scales, and seniority systems for male and female employees.
After the filing of answers, Murphy filed a cross-claim against the unions in which it asserted that the unions were solely liable for the discrimination complained of and that if Murphy was found liable, it had a right of contribution against the unions. Prior to trial a settlement was reached by Murphy and the plaintiff class. The settlement was approved by the district court. It provided for the payment of $548,000 in damages and $100,000 in attorneys’ fees. The payment was to be made in three installments with six percent interest on the deferred payments; $100,000 of the $548,-000 was allocated to the Equal Pay Act charge.
Murphy continued to press for contribution from the unions and eventually settled with Local 940 for $4,146, the total amount in Local 940’s treasury. Trial proceeded on [251]*251Murphy’s claim against the International and Local 249. The district court concluded that Murphy and the defendant unions had violated Title VII and that they were equally liable for the discrimination and thus equally responsible for the financial loss of the plaintiffs. After dividing the damages, the court entered judgment against the International in the amount of $242,337. Glus v. G. C. Murphy Co., Civ. No. 71-264 (W.D.Pa. Apr. 29, 1976), reprinted in Joint Appendix at 124a-78a [hereinafter Glus I].
The International appealed from that judgment asserting that the district court did not have jurisdiction over it under Title VII because the International had not been named in the complaint filed by the plaintiffs with the Equal Employment Opportunity Commission (EEOC). It also asserted that no right of contribution could be claimed for violations of Title VII or the Equal Pay Act. In the first appeal we held that Murphy had no right of contribution under the Equal Pay Act, Denicola v. G. C. Murphy Co., 562 F.2d 889 (3d Cir. 1977), but remanded for further proceedings on the issue of whether the district court had jurisdiction under Title VII. Glus v. G. C. Murphy Co., 562 F.2d 880 (3d Cir. 1977). On remand the district court found that the plaintiff had not named the International in the EEOC complaint but that the omission did not result in an absence of jurisdiction. Glus v. G. C. Murphy Co., Civ. No. 71-264 (W.D.Pa. Feb. 14, 1979), reprinted in Joint Appendix at 833a-40a [hereinafter Glus II]. The International appeals for a second time challenging the district court’s conclusions on jurisdiction and challenging the district court’s earlier decision on the right of contribution. Murphy cross-appeals arguing that the district court did not properly calculate the amount due under the right of contribution.
II. Title VII Jurisdiction
In the first appeal we enumerated four factors that should be considered in determining whether the district court had jurisdiction under Title VII. They were:
1) whether the role of the unnamed party could through reasonable effort by the complainant be ascertained at the time of the filing of the EEOC complaint; 2) whether, under the circumstances, the interests of a named [party] are so similar as the unnamed party’s that for the purpose of obtaining voluntary conciliation and compliance it would be unnecessary to include the unnamed party in the EEOC proceedings; 3) whether its absence from the EEOC proceedings resulted in actual prejudice to the interests of the unnamed party; 4) whether the unnamed party has in some way represented to the complainant that its relationship with the complainant is to be through the named party.
562 F.2d at 888. This four-prong test is not a mechanical one; no single factor is decisive. Instead each factor should be evaluated in light of the statutory purposes of Title VII and the interests of both parties. The district court applied these factors and concluded that it had jurisdiction. We agree.
The interests of Local 940, which was named in the EEOC complaint, and the International are identical in all significant aspects, and thus the International was not harmed by its absence from the EEOC proceedings. Their liability arises from their participation in the same collective-bargaining agreements. The International was the sole union signatory to the collective-bargaining agreement for a portion of the period where discrimination was found to have taken place; later both the International and Local 940 signed the agreements. The International’s representative was the chief union negotiator at many of the negotiation sessions. The International’s interests were vigorously litigated by Local 940 at the EEOC proceedings. Local 940 stood firm in its denial of liability. Further, both the International and Local 940 were represented by the same attorney, Emil E. Narick, Esq., in the district court proceeding until Murphy filed its claim for contribution.
The plaintiffs’ interests were not harmed by the International’s absence in the EEOC process. If a settlement had been reached during the EEOC proceeding, complete re[252]*252lief could have been obtained from the defendants then present. We also note the finding of the district court that the close relationship between the International and Local 940 could have led the plaintiff to reasonably assume that the interests of both unions were to be represented by Local 940. Glus II, App., at 838a-39a. Finally, we agree with the district court that the conciliation process was not rendered less effective because of the absence of the International. The settlement agreement was not reached until the federal court action had begun, at which time the International was a party to the litigation.
We will therefore affirm the district ; court’s decision on the jurisdictional issue.1
III. Right to Contribution
In its cross-claim Murphy requested contribution for what it asserted was the International’s share of the damages Murphy had paid in the settlement agreement. By its express terms Title VII does not provide for a right of contribution. Murphy asserts that nevertheless a right of contribution exists in the federal common law arising from Title VII. It is to this claim that we now turn.
A.
At the outset we note our disagreement with the International and the dissent that no right of contribution exists in the federal common law because there is an “established rule that contribution would not be implied in the absence of a statutory provision.” At 267. Initially most American courts held that there was no right of contribution under the common law, relying on the English decision Merryweather v. Nixan, 8 Term R. 186, 101 Eng.Rep. 1337 (K.B. 1799). See, e. g., Union Stock Yards Co. v. Chicago, Burlington, & Quincy Railroad Co., 196 U.S. 217, 25 S.Ct. 226, 49 L.Ed. 453 (1905). This prohibition resulted from the belief that a wrongdoer should not be able to shift the responsibility of his actions to the shoulders of another. The rule prohibiting contribution has come into disrepute. It is now widely recognized that fundamental fairness demands a sharing of the liability. Without a right of contribution a wrongdoer may escape liability for his actions because of the happenstance of the plaintiff’s choice of defendants. See Prosser, The Law of Torts, § 50 (4th ed. 1971). See also Sellers, Contribution in Antitrust Damage Actions, 24 Vill.L.Rev. 829, 855-63 (1979) (reviewing state law on contribution). The vast majority of the states have now rejected the prohibition either by statute, e. g., Del.Code tit. 10, §§ 6301-08; Pa.Cons.Stat.Ann. tit. 42 §§ 8323-27 (Purdon 1979), or by judicial action. E. g., Knell v. Feltman, 174 F.2d 662 (D.C. Cir. 1949); State Farm Auto Insurance Co. v. Continental Casualty Co., 264 Wis. 493, 59 N.W.2d 425 (1953).
The International argues that the prohibition still exists in federal law, relying on Halcyon Lines v. Haenn Ship Ceiling & Refitting Corp., 342 U.S. 282, 72 S.Ct. 277, 96 L.Ed. 318 (1952). Cf. Olson Farms, Inc. v. Safeway Stores, Inc., 1979 — 2 Trade Cases K 62,995 (10th Cir. 1979) (relying on Halcyon Lines to deny contribution under federal anti-trust laws). We do not agree. Halcyon Lines was an action for contribution arising under the admiralty jurisdiction of the federal courts. The Court found the claim inconsistent with the Longshoremen’s and Harbor Workers’ Compensation Act, 33 [253]*253U.S.C. §§ 901-944. It denied the claim and stated, “[I]n the absence of legislation, courts exercising a common-law jurisdiction have generally held that they cannot on their own initiative create an enforceable right of contribution as between joint tortfeasors.” 342 U.S. at 285, 72 S.Ct. at 279. For a number of years this language was relied upon to deny claims for contributions brought under federal law. See, e. g., Goldlawr, Inc. v. Shubert, 276 F.2d 614, 616 n. 3 (3d Cir. 1960) (anti-trust law). However, in 1974 the Supreme Court held that its holding was not as far-reaching as the language suggests. In Cooper Stevedoring Co., Inc. v. Fritz Kopke, Inc., 417 U.S. 106, 111-13, 94 S.Ct. 2174, 2177-78, 40 L.Ed.2d 694 (1974) , the Court explained that it had denied contribution in Halcyon Lines only because under the facts of that case contribution was inconsistent with the Harbor Workers’ Act. It stated:
[W]e think Halcyon stands for a more limited rule than the absolute bar against contribution . . . . On the facts of this case, then, no countervailing considerations detract from the well-established maritime rule allowing contribution between joint tortfeasors.
The Supreme Court has yet to review a contribution claim in a case outside of the admiralty context since Cooper Stevedoring. But a number of lower courts have read Cooper Stevedoring as supporting rights of contribution in federal common law claims. E. g., Professional Beauty Supply Inc. v. National Beauty Supply, Inc., 594 F.2d 1179 (8th Cir. 1979) (anti-trust law); Kohr v. Allegheny Airlines Inc., 504 F.2d 400 (7th Cir. 1974), cert. denied, 421 U.S. 978, 95 S.Ct. 1980, 44 L.Ed.2d 470 (1975) (aviation law). But see Olson Farms, Inc. v. Safeway Stores, Inc. (denying right of contribution in anti-trust law). Thus, Cooper Stevedoring provides positive support for our conclusion that a federal common law right of contribution exists.
B.
As we noted above, no right of contribution is expressly provided for in Title VII. This does not, however, end our inquiry. For this does not necessarily reflect a congressional intention to deny a right of contribution. Rather it reflects the probability that contribution, although of considerable importance, was not contemplated by the drafters of the legislation. We must therefore inquire into the interstices of Title VII to respond to Murphy’s claim.
The responsibility of federal courts to define the body of federal common law which arises from the interstices of federal legislation has been established by a number of Supreme Court decisions. E. g., Illinois v. Milwaukee, 406 U.S. 91, 92 S.Ct. 1385, 31 L.Ed.2d 712 (1972) (federal common law right of nuisance recognized and applied to the pollution of interstate waters); Textile Workers v. Lincoln Mills, 353 U.S. 448, 77 S.Ct. 912, 1 L.Ed.2d 972 (1957) (federal labor law); Texas & Pacific Railway v. Rigsby, 241 U.S. 33, 36 S.Ct. 482, 60 L.Ed. 874 (1916) (Safety Appliance Act).
The scholarly debate about the power of the federal courts to recognize common law claims rages as does the debate on the source of that power and the extent to which it can be exercised. See, e. g., Ely, The Irrepressible Myth of Erie, 87 Harv.L. Rev. 693 (1974); Friendly, In Praise of Erie — And the New Federal Common Law, 39 N.Y.U.L.Rev. 383 (1964); Bickel & Wellington, Legislative Purpose and the Judicial Process, 71 Harv.L.Rev. 1 (1957). Yet, in spite of the stridency of the debate, two principles firmly and resolutely emerge. First, there is a federal common law, Illinois v. Milwaukee, 406 U.S. at 98-102, 92 S.Ct. at 1390-1392. Second, in some circumstances federal common law causes of action arise from the interstices of congressional acts. See, e. g., Textile Workers v. Lincoln Mills. Common law actions arising from federal legislation have been recognized in a variety of circumstances, including instances when the common law establishes remedies and standards not set forth in the legislation, but necessary for the fulfillment of the legislative purpose, e. g., Illinois v. Milwaukee; Textile Workers v. Lincoln Mills, and instances where the com[254]*254mon law provides a cause of action for an individual who has been harmed by the violation of the federal statute. E. g., J. I. Case Co. v. Borak, 377 U.S. 426, 84 S.Ct. 1555, 12 L.Ed.2d 423 (1964); Texas & Pacific Railway v. Rigsby. In our review of the literature and the case law we discern two types of cases which establish the framework for our determination of whether a common law right of contribution arises from the interstices of Title VII.
The first are cases in which the common law provides remedies or standards when legislation related to the petitioner’s claim does not address the specific situation presented. These cases are illustrated by the seminal decision, Textile Workers Union v. Lincoln Mills. In Lincoln Mills the plaintiff union charged Lincoln Mills with violating a collective-bargaining agreement. The Supreme Court held that the standards for evaluating the claim were to be found in the federal common law. The Court reasoned that when Congress granted to the federal courts jurisdiction over controversies involving labor organizations in the Labor Management Relations Act, 29 U.S.C. §§ 141-187, it wanted those controversies to be resolved by a federal common law.- The Court argued that a uniform federal law was necessary to achieve the purposes of the Act. Although it made no extensive analysis of the source of its power to fashion this body of common law, it noted, “[i]t is not uncommon for federal courts to fashion federal law where federal rights are concerned.” 353 U.S. at 457, 77 S.Ct. at 918. The exact contours of this body of common law was to be determined by a review of the applicable legislation.
The Labor Management Relations Act expressly furnishes some substantive law. It points out what the parties may or may not do in certain situations. Other problems will lie in the penumbra of express statutory mandates. Some will lack express statutory sanction but will be solved by looking at the policy of the legislation and fashioning a remedy that will effectuate that policy. The range of judicial inventiveness will be determined by the nature of the problem.
Id.
A similar analysis was used in Illinois v. Milwaukee. In that case the Supreme Court was presented with a common law nuisance action brought by the State of Illinois. Illinois brought the action against four cities of Wisconsin, the Sewerage Commission of the City of Milwaukee, and the Sewerage Commission of the County of Milwaukee in an attempt to abate the alleged pollution of Lake Michigan, a body of interstate water. The Court found that Congress had a strong interest in “the quality of the aquatic environment as it affects the conservation and safeguarding of fish and wildlife,” 406 U.S. at 102, 92 S.Ct. at 1392, evidenced by legislation such as the Federal Water Pollution Control Act, 62 Stat. 1155, as amended (presently codified at 33 U.S.C. §§ 1251 et seq.) and the Fish and Wildlife Act of 1956, 70 Stat. 1119, 16 U.S.C. § 742a. Undaunted by the absence of an express cause of action in any of these acts covering Illinois’ claim, the Court held that one existed in the federal common law. It stated:
The remedy sought by Illinois is not within the precise scope of remedies prescribed by Congress. Yet the remedies which Congress provides are not necessarily the only federal remedies available. “It is not uncommon for federal courts to fashion federal law where federal rights are concerned.” Textile Workers v. Lincoln Mills, 353 U.S. 448, 457, [77 S.Ct. 912, 918, 1 L.Ed.2d 972.]
Id. at 103, 92 S.Ct. at 1392. See also National Sea Clammers Association v. City of New York, 616 F.2d 1222, 1235 (3d Cir. 1980). (After considering the rationale of Illinois v. Milwaukee, this court concluded that there is a “federal common law of nuisance [which] may be enforced by private plaintiffs.”)
The second group of cases are similar yet distinctive. They deal with the specific issue of whether a federal common law action may be brought by an individual who has been harmed by a violation of legislation designed to protect that individual. [255]*255The earliest Supreme Court decision of that nature seems to be Texas & Pacific Railway v. Rigsby. The Rigsby Court held:
A disregard of the command of the statute is a wrongful act, and where it results in damage to one of the class for whose especial benefit the statute was enacted, the right to recover the damages from the party in default is implied, according to a doctrine of the common law.
241 U.S. at 39, 36 S.Ct. at 484. See generally Note, Implied Civil Liability and the Trust Indenture Act, 52 Tul.L.Rev. 299, 309 (1978).
This issue has been the subject of a number of Supreme Court decisions, and the applicable analysis has become highly developed. In Cort v. Ash, 422 U.S. 66, 95 S.Ct. 2080, 45 L.Ed.2d 26 (1975), the Supreme Court set forth a four-prong test:
First, is the plaintiff “one of the class for whose especial benefit the statute was enacted” — that is, does the statute create a federal right in favor of the plaintiff? Second, is there any indication of legislative intent, explicit or implicit, either to create such a remedy or to deny one? Third, is it consistent with the underlying purposes of the legislative scheme to imply such a remedy for the plaintiff? And finally, is the cause of action one traditionally relegated to state law, in an area basically the concern of the States, so that it would be inappropriate to infer a cause of action based solely on federal law?
Id. at 78, 95 S.Ct. at 2088 (emphasis in original; citations omitted). As we have noted, the four-prong analysis of Cort v. Ash is designed to “guide the courts in determining legislative intent.” National Sea Clammers Association v. City of New York, 616 F.2d at 1229, citing, Touche, Ross & Co. v. Redington, 442 U.S. 560, 99 S.Ct. 2479, 61 L.Ed.2d 82 (1979), and Trans America Mortgage Advisors, Inc. v. Lewis, 444 U.S. 11, 100 S.Ct. 242, 62 L.Ed.2d 146 (1979). The inquiry in a right to contribution claim is somewhat different because the party requesting contribution, by definition, will never be a member of the class protected by the legislation. Indeed that party will always be a member of the class from whom the “especial” class was to be protected. Northwest Airlines, Inc. v. Transport Workers, 606 F.2d 1350, 1354 (D.C. Cir. 1979), cert. granted, 445 U.S. 902, 100 S.Ct. 1077, 63 L.Ed.2d 318 (1980).
Although the question presented in each of these cases is different from Murphy’s claim we find them helpful in our analysis. For in each of these cases the Court turns to the relevant legislation to determine whether the common law action exists, and ascertains the congressional intent as to both the underlying goals of the legislation and the specific action presented. It is this methodology which we will use in our evaluation of Murphy’s contribution claim.
C.
In our review of the legislative history of Title VII we have not found any materials which explicitly indicate whether or not Congress intended for a right of contribution to exist. The absence of such an explicit reference does not end our inquiry, for “the legislative history of a statute that does not expressly create or deny a private remedy will typically be equally silent or ambiguous on the question.” Cannon v. University of Chicago, 441 U.S. 677, 694, 99 S.Ct. 1946, 1956, 60 L.Ed.2d 560 (1979). As we are “obliged to find an answer [we] must resort to materials from which the Congressional intent can only be inferred.” United Parcel Service, Inc. v. United States Postal Service, 604 F.2d 1370, 1383 (3d Cir. 1979) (Higginbotham, J., dissenting).
The express terms of Title VII demonstrate a congressional intent that unions be held financially liable with employers for unlawful employment practices. Section 703(a), 42 U.S.C. § 2000e-2(a), proscribes employer discrimination, and section 703(c)(3), 42 U.S.C. § 2000e-2(c)(3), holds a union liable not only for discriminatory actions in which it independently engages, but also when it “cause[s] or attempt[s] to cause an employer to discriminate against an individual . . . ” Furthermore, section [256]*256706(g) expressly states that a court may award damages for “back pay (payable by the employer, employment agency, or labor organization), ...” 42 U.S.C. § 2000e-5(g). Under these provisions the union and the employer may be held jointly liable when the unlawful activity was a joint undertaking. See Evans v. Sheraton Park Hotel, 503 F.2d 177 (D.C. Cir. 1974) (employer, local union and international held jointly liable for back pay and attorneys’ fees); Johnson v. Goodyear Tire & Rubber Co., 491 F.2d 1364 (5th Cir. 1974) (company and union held jointly liable for back pay and attorney’s fees); Commonwealth of Pennsylvania v. Local 542, International Union of Operating Engineers, 469 F.Supp. 329 (E.D.Pa.1978) (union and company held jointly liable for injunctive relief). These provisions reflect a statutory policy that the responsibility for monetary relief should be borne by both unions and employers to the extent that they are responsible for violations of Title VIL A right of contribution would achieve this goal. In contrast, a holding that there is no right of contribution under Title VII would release some individuals from liability.
Other policies underlying Title VII would be served by a right of contribution. In Albemarle Paper Co. v. Moody, 422 U.S. 405, 417, 95 S.Ct. 2362, 2371, 45 L.Ed.2d 280 (1975) (footnote omitted), the Supreme Court emphasized that Title VIPs “primary objective [is] a prophylactic one.” The Court stated: Id. at 417-18, 95 S.Ct. at 2371-72, quoting United States v. N. L. Industries, Inc., 479 F.2d 354, 379 (8th Cir. 1973). Under a rule of contribution “[b]oth union and employer will know that they both must be vigilant to eschew unlawful discrimination and that the employee’s predilections as to whom to sue will not insure either immunity from the mandates of the law.” Northwest Airlines, Inc. v. Transport Workers Union of America, 14 E.P.D. 117730, 5596 (D.D.C. 1977), rev’d on other grounds, 606 F.2d 1350 (D.C. Cir. 1979), cert. granted, 445 U.S. 902, 100 S.Ct. 1077, 63 L.Ed.2d 318 (1980). Cf. Globus, Inc. v. Law Research Service, Inc., 318 F.Supp. 955, 958 (S.D.N.Y.), aff’d, 442 F.2d 1346 (2d Cir. 1971), cert. denied, 404 U.S. 941, 92 S.Ct. 286, 30 L.Ed.2d 254 (1971) (implied right of contribution would strengthen “the deterrent impact of the securities law”).
It is the reasonably certain prospect of a back pay award that “providefs] the spur or catalyst which causes employers and unions to self-examine and to self-evaluate their employment practices and to endeavor to eliminate, so far as possible, the last vestiges of an unfortunate and ignominious page in this country’s history.”
A right of contribution would also serve the Title VII policy of favoring conciliation and settlement of these claims. “[C]ooperation and voluntary compliance [are] the preferred means for achieving” the goal of equality of employment opportunities. Alexander v. Gardner-Denver Co., 415 U.S. 36, 44, 94 S.Ct. 1011, 1017, 39 L.Ed.2d 147 (1974). This is shown by the facts of this case. If Murphy had felt that it had no right of contribution against the unions it might have been unwilling to reach a settlement with the plaintiffs. It might have chosen instead to proceed with the litigation so that the unions would be held responsible for a share of the damages. Further, the contribution rule prevents a plaintiff from becoming unjustly enriched either by collusive activity with one of the defendants, or by threatening one defendant that the suit will be brought only against it, thereby forcing an unjustified settlement. See Note, Settlement in Joint Tort Cases, 18 Stan.L.Rev. 486, 490 (1966).2
[257]*257A right of contribution would implement the congressional intent to hold both unions and employers liable for unlawful employment practice and would aid the conciliation and settlement goals of Title VII. Thus, we hold that a federal common law right of contribution exists when a defendant charged with a violation of Title VII settles with a plaintiff prior to trial for the full amount of damages and requests contribution from a non-settling co-defendant who is jointly liable.
D.
The dissent argues that by choosing, in this case, the rule of decision which we believe to be the better one we are unjustifiably performing a legislative function. It concedes that we are dealing with a subject matter requiring a uniform federal rule of decision. Thus we and the dissent agree that adoption of a contribution rule is no invasion of an area which state lawmaking authority, legislative or judicial, can claim as its own. The dissent’s complaint is that by adopting what we think is the better rule of decision we are invading the exclusive preserve of Congress. If we were to announce a federal rule of decision implied from a constitutional provision,3 and thus arguably beyond the future control of Congress there might be some merit to the dissent. See Monaghan, Forward: Constitutional Common Law, 89 Harv.L.Rev. 1 (1975). But the rule of decision which we have found to be preferable could be changed by Congress tomorrow.
The difficulty with the dissent’s argument on legislative function is that it concedes “If it was clear, as my colleagues apparently believe, that a right of contribution would strengthen the deterrent impact of Title VII, then there might be a judicial responsibility to make those rules which are needed to effectuate the significant national policy represented by the statute.” At 268. There are countervailing arguments, and the policy choice is a difficult one. But the litigants before us have tendered the issue, and its closeness does not absolve us from the obligation to decide it. Nor does our action become an impermissible encroachment on the legislative branch, merely because of the difficulty of the issue presented. Whether we reject or adopt a contribution rule we must make a choice.
If we were to be convinced that a rule prohibiting contribution better served the purpose of Title VII our adoption of that rule would stand in relationship to Congress on exactly the same footing. The logic of the argument that adoption of a rule prohibiting rather than permitting contribution would be less legislative escapes us. Cer.tainly the party whose claim for contribution was rejected would not think we acted any less legislatively in rejecting it. Reliance on deference to the legislative process cannot conceal the fact that the dissent has made such a choice.
IV. Calculation of Liability
Each of the parties argues that if we hold that a right of contribution exists we should order a modification of the judgment because the district court did not apply the correct rules of law when it calculated the International’s liability. We do not agree.
Using the $648,000 settlement figure which had been reached by Murphy and the class members as the starting point of its calculations, the district court allocated $529,752 to the Title VII claim. It held Murphy responsible for $264,876 of the Title VII liability and the unions — the International, Local 940 and Local 249 — jointly responsible for the remaining $264,876. The court then subtracted from the unions’ share a proportion which it allocated to Local 249, $18,393, and the $4,146 which Local 940 had paid Murphy.4 Judgment [258]*258against the International was entered in the amount of $242,337.
The International argues that it should have been assessed for only 50% of the liability which .was attributed to the unions because it had been held equally liable with the local unions. We do not agree. The district court found Murphy responsible for half of the Title VII liability and the unions collectively responsible for the other half. The court held the unions liable as a group for half of the damages because they had acted jointly in the collective-bargaining negotiations with Murphy. It was therefore reasonable when it became apparent that Local 940 could pay only $4,146, for the court to hold the International’s responsible for the remaining portion.
Murphy argues that the district court should have included in its calculations the interest Murphy paid because it paid the plaintiffs in three installments. We do not agree. The deferred payment schedule benefitted Murphy as it had use of the money during that period. It would have been improper for the court to have permitted Murphy to recoup from the International the monies it paid the plaintiffs for that benefit.
Murphy also objects to the district court’s decision not to award it prejudgment interest. The general rule is that when the damages are ascertainable “with mathematical precision prejudgment interest is awardable as of right.” Eazor Express, Inc. v. International Brotherhood of Teamsters, 520 F.2d 951, 973 (3d Cir. 1975), cert. denied, 424 U.S. 935, 96 S.Ct. 1149, 47 L.Ed.2d 342 (1976). If, however, the claim is not for a liquidated sum, the decision on whether the award interest is within the sound discretion of the court. Id.; Thomas v. Duralite Co., Inc., 524 F.2d 577, 589 (3d Cir. 1975). The district court did not abuse its discretion by not awarding pre-judgment interest. The International did not unduly delay the litigation. An award of interest here would punish the International unfairly because it exercised its right to proceed to trial.
The International - argues that its liability should be recalculated because the damage settlement included monies for all females who were employed from July 2, 1965 to January 31, 1971, even though a number of those employees had terminated their employment in the years 1965 through 1968. For the first time in this litigation it argues that the claims of these terminated [259]*259female employees were erroneously computed into the settlement because those employees could not have filed timely charges in July of 1969 when the EEOC charges underlying this case were filed. The International argues that these claims must be excluded from any back pay calculations since those former employees cannot be members of the plaintiff class relying on Wetzel v. Liberty Mutual Insurance Co., 508 F.2d 239, 246 (3d Cir.), cert. denied, 421 U.S. 1011, 95 S.Ct. 2415, 44 L.Ed.2d 679 (1975). This case is distinguishable from Wetzel because here the International stated explicitly on the record that it had “ ‘no objection to the amount of the settlement and/or as to the determination of the legal fees . ’ ” Glus I, App., at 173a. (emphasis added) By agreeing to the amount of the settlement (though of course contesting its liability) the International shrewdly limited its maximum exposure to Title VII damages. The company could have argued that the Equal Pay Act settlement should have been less and the Title VII damages more than $448,000. We adopt the trial judge’s response that it is now “too late to raise such an objection.”
The International’s objections must be rejected. On October 2, 1971, at the hearing held by the court on the consent decree, the International, on the record, stated that it had “no objection to the amount of the settlement and/or as to the determination of the legal fees . . ” while it, of course, reserved the right to challenge Murphy’s claim for contribution. (Tr. 11). At the hearing, Local 249 indicated that it was adopting the same position. Both of these unions had notice of every hearing and conference held by the court on the settlement procedures, and no objection of any kind was lodged. It is too late to raise such an objection.
Further, the settlement figure does not reflect a detailed calculation of the damages due each member of the class as would have been required at a trial. The district court noted that, if calculated, the defendants’ liability may have been as high as $800,000. Id. at 176a. The settlement reflects a compromise reached by Murphy and the plaintiff class and it reflects not only mathematical calculations on lost wages, but also the strengths and weaknesses of the legal arguments which could have been made for either party or varying members of the class. We therefore will affirm the district court’s reliance on the settlement figure in its calculation.
V.
For the foregoing reasons, we will affirm the judgment of the district court.