¶ 1 Precision Heavy Haul, Inc. (“Precision”) appeals from the trial court’s denial of prejudgment interest on a judgment in Precision’s favor following a jury trial. The trial court ruled that because the defendant, Trail King Industries, Inc. (“Trail King”), had raised comparative fault as a defense, Precision’s claim was for an unliquidated sum and not subject to prejudgment interest. In a separate unpublished memorandum decision, we address and affirm as to all issues raised in Trail King’s cross-appeal, which challenges the admission of expert testimony on Precision’s behalf as well as the process for selecting jury pools in Maricopa County superior courts. For reasons that follow, however, we reverse the ruling denying prejudgment interest and remand for further proceedings.
BACKGROUND
¶ 2 Precision filed suit against Trail King and Carlisle Companies, Inc., alleging that Trail King had manufactured and sold to Precision a trailer for transporting heavy loads, that the trailer’s negligent design and manufacture caused it to fail, and that in doing so, the trailer and the energy transformer being transported on it were damaged. Precision alleged claims of negligence, strict liability, and breach of warranty. Trail King’s answer asserted that Precision had negligently used or altered the trailer and that its damages “were caused or contributed to by [Precision’s] own comparative negligence or assumption or [sic] risk which bar[red] or reduce[d] on a comparative basis” its claims.
¶ 3 At trial, Precision’s owner testified that his company had incurred $694,550.87 in damages and offered testimony by two experts concerning the cause of the accident that damaged the transformer. The jury returned a verdict finding Trail King 100% at fault and awarding $694,550.87 in damages to Precision. The sole issue raised by Precision’s appeal is the court’s denial of prejudgment interest. We have jurisdiction of the appeal pursuant to Arizona Revised Statutes (“A.R.S.”) section 12-2101(B) (2003).
DISCUSSION
Denial of Prejudgment Interest
¶ 4 A party’s entitlement to prejudgment interest presents a question of law for our
de novo
review.
Gemstar Ltd. v. Ernst & Young,
¶ 5 An exhibit summarizing Precision’s damages was admitted at trial. The listed damages were: rigging and crew expenses in the amount of $28,590.00; crane and salvage crew expenses in the amount of $14,768.02; payment to Precision’s customer for damages to the energy transformer in the amount of $495,000.00; and funds owed to Precision but set off by its customer in the amount of $156,192.85. These requested damages totaled $694,550.87. At trial, Trail King ultimately did not challenge the accuracy of the total damages. Instead, it denied any negligence but asked, if found negligent, that the jury attribute a percentage of comparative fault to Precision, thereby reducing its own liability.
¶ 6 Rejecting any attribution of fault to Precision, the jury returned a verdict finding Trail King 100% at fault and awarding Precision damages in the exact amount requested. Precision then moved for a determination of its right to prejudgment interest. It argued that a claim is liquidated “if the evidence furnishes data which, if believed, makes it possible to compute the amount with exactness, without reliance upon opinion or discretion.”
Employers Mut. Cas. Co.,
¶ 7 Trail King objected, arguing that when a jury must exercise its discretion to apportion fault, the claim is not liquidated. Without Arizona precedent on point, it cited a South Dakota case in which the supreme court there upheld the denial of prejudgment interest in a construction defect ease in which the plaintiff was found to be thirty percent at fault.
1
S. Dakota Bldg. Auth. v. Geiger-Berger Assoc.,
¶ 8 Trail King also relied upon
Wisper Corp. N.V. v. California Commerce Bank,
¶ 9 Trail King also argued that because Precision’s damages included a number of “estimated and indefinite” items subject to jury scrutiny for reasonableness and causation, the damages were unliquidated. Precision, of course, disagreed and replied that any uncertainty over
liability
for the accident should not bar prejudgment interest if the amount of damages was certain, citing
Banner Realty, Inc. v. Turek,
¶ 10 The tidal court acknowledged differing approaches taken by our sister states in cases involving comparative fault but found Wisper persuasive 3 and concluded that because “the jury was charged with deciding comparative fault in a manner that made Plaintiffs damages wholly dependent upon that sliding scale ... the award [was] unliq-uidated.” Thus, because of the comparative negligence defense, the court awarded interest on Precision’s damages only from the date of the verdict.
¶ 11 Although the impact of comparative negligence upon liquidated damages is a novel issue in Arizona, our ease law has established that uncertainty about a defendant’s liability, even when a trial is necessary
¶ 12 We reached a similar result in
Alta Vista Plaza,
¶ 13 On appeal, we held that because the “repair costs and architect’s fees were readily ascertainable by accepted standards of valuation,” the tort claim was liquidated for purposes of prejudgment interest even though “the case had to be tried.”
Id.
at 83,
¶ 14 In the instant case, although Trail King hotly disputed the extent of its liability for Precision’s damages, the amount of damages Precision had suffered easily could be calculated from the uncontested evidence. The various amounts paid to its client and crew were known, provided to Trail King, and not challenged. The primary issue was not whether Precision had been damaged or in what amount, but what percentage of the damages Trail King would have to pay. Given that the jury awarded Precision the entire amount of damages sought, only an award of prejudgment interest on those damages will make Precision whole.
See id.,
¶ 15 Our analysis is similar to the Ninth Circuit’s view of California law regarding a plaintiffs entitlement to prejudgment interest. The court held that “damages are considered certain or capable of being made
¶ 16 In addition, the Ninth Circuit cited with approval
E.L. White, Inc. v. City of Huntington Beach,
¶ 17 Here, several of the damage components claimed by Precision were capable of straightforward calculation, which Trail King did not challenge. Therefore, Precision was entitled to prejudgment interest on those components. Interest generally is calculated “from the date the claim becomes due” or a party becomes obligated to pay.
Gemstar Ltd.,
¶ 18 We also note that a defendant’s general attack on the reasonableness of a plaintiffs claimed damages does not necessarily thereby render those damages unliquidated. Here, Trail King focused its reasonableness challenge on the $156,192.87 which Precision said was set off by its customer. When the superior court ruled that, because the jury had to apportion fault, Precision’s entire claim was unliquidated, the court did not address whether Trail King’s challenge of the reasonableness of the customer setoff portion of the damages rendered that portion unliquidated. Thus, we also remand to the superior court the resolution of that question.
¶ 19 For the foregoing reasons, we reverse the superior court’s denial of prejudgment interest to Precision on the amounts awarded for damages to the transformer as well as for crew, rigging, and salvage expenses. We also remand the issue of whether Trail King’s challenge of the reasonableness of the customer setoff portion of the judgment rendered that portion unliquidated. We award Precision, as the prevailing party, its costs on appeal. A.R.S. § 12-341 (2003).
Notes
. The statute at issue provided: “Every person who is entitled to recover damages certain, or capable of being made certain by calculation, and the right to recover which is vested in him upon a particular day, is entitled also to recover interest thereon from that day...."
. In a dissenting opinion. Judge McDonald doubted the wisdom of a focus on the gap between damages sought and damages won as a "slippery slope” and noted that in this case, the damages were certain and the real dispute was how to allocate fault among the parties.
Id.
at 150-51,
. Although we disagree with the outcome in Wis-per, we agree with many of the fundamental principles expressed. The court noted that a defendant's "denial of liability [did] not make damages uncertain.” Id. at 146. Instead, damages were certain if the parties' dispute centered on liability rather than on the basis for computing damages. Id. The court accepted that prejudgment interest is to make the injured party whole and to compensate "for the accrual of wealth that could have been produced during the period of loss.” Id. at 148. It cited prior cases that had held if the amount of damage required "a judicial determination based upon conflicting evidence and [was] not ascertainable from truthful data supplied by the claimant to his debtor,” id., the plaintiff was not entitled to prejudgment interest. Id.
