(dissenting).
[¶ 53.] I join the dissent of Chief Justice Gilbertson. I also write specially to emphasize the material disputes of fact that exist in this case and to express my belief that the Court has misinterpreted and incorrectly applied SDCL 19-18-6 (Fed R Evid 1006) governing summaries.
Material Issues of Disputed Fact
[¶ 54.] One need not read more than the opening passage of the Bank’s own brief to resolve this appeal. In that passage, the Bank unequivocally demonstrates the existence of material issues of disputed fact on Scotts’ affirmative defense of payment. The Bank’s Statement of the Facts expressly concedes the point stating that:
This case involves a dispute over the amount of principal due on a promissory note delivered to the Bank by the Scotts in August of 1985. The Bank contended that at maturity the Scotts owed $109,948.79 plus interest on the note, while the Scotts asserted that the note *660was paid in full. This seemingly straightforward matter is complicated because neither the Scotts nor the Bank have complete records of payments made on the note.
Considering this statement alone, we should reverse the summary judgment. Never before has this Court permitted summary judgment in such circumstances: especially not when the trial court had to make credibility determinations about disputed factual assumptions underlying each side’s payment records (described by both parties as amortization schedules).
[¶ 55.] The trial court concluded that Bank was entitled to summary judgment because it found that the Scotts’ amortization contained “obvious glaring errors.” On the other hand, the trial court apparently found the Bank’s amortization credible despite missing records and alleged errors. This Court compounds the problem by further finding that “[i]t was reasonable for the trial court to rely on the Bank’s balance.... ” See supra note 7 (emphasis added). In my view, this type of fact finding, expressly finding the reasonableness of disputed evidence, has no place in summary judgment proceedings.
[¶ 56.] The Court, therefore, attempts to distinguish our precedent prohibiting fact finding in summary judgment proceedings by noting that this case involves payment, which is an affirmative defense. However, the Court’s error is illustrated by Wright, Miller and Kane’s discussion of summary judgment in cases involving defenses. That treatise recognizes that even though a motion for summary judgment may be used to test the sufficiency of a defendant’s defense:
A [plaintiff] is entitled to summary judgment only when no genuine issue of material fact exists, the papers on the motion demonstrate the right to relief, and every one of the defenses asserted legally are insufficient. Since a single valid defense may defeat recovery, however, [plaintiffs] motion for summary judgment should be denied when any defense presents significant fact issues that should be tried.
10B Charles Alan Wright, Arthur R. Miller & Mary Kay Kane, Federal Practice and Procedure § 2734 (3d ed 1998) (emphasis added). Accordingly, if a fact issue existed on the payment defense, summary judgment should have been denied, and the trial court’s resolution of the payment dispute should have been determined at a trial. Simply stated, the Scotts’ ultimate trial burden of persuasion under SDCL 57A-3-308 is irrelevant. It is irrelevant because the only question on the motion for summary judgment is whether any material dispute of fact exists on the payment defense.
[¶ 57.] Additionally, even if a fact resolution of the payment dispute were permitted in summary judgment proceedings, the Bank’s own showing does not affirmatively demonstrate its entitlement to relief. It does not because the Bank’s own amortization schedule is subject to the same infirmities the Court uses to invalidate the Scotts’ amortization schedule. Specifically, this Court disallows consideration of Scotts’ amortization because of their inability to produce the records15 used to construct their schedule. However, Bank concedes that it also lost underlying documentation supporting the outstanding principal claimed on its schedule. Indeed, in its Statement of Material Facts filed in support of its motion, the Bank expressly concedes that “[a]pparently, the records of any payments that had been made prior to the execution of the Third Allonge in Octo*661ber of 1988 bad been destroyed when Western Bank merged into First Bank in the late 1980s.”
[¶ 58.] Moreover, the Bank’s other supporting submissions demonstrate that its claim to $109,948.79 in principal is inconsistent and uncertain. The Bank’s claim is inconsistent because it is based upon two affidavits of Michael J. Porcello, a Bank Vice President. However, the claims made in those affidavits are inconsistent. In his first affidavit, Porcello claimed entitlement to $109,948.79. However, in his second affidavit, he attached a Bank amortization schedule, purportedly prepared from Bank records, claiming $111,258.61. Nevertheless, the trial court found for the Bank in the amount of $109,948.79.
[¶ 59.] The Bank also concedes that there is record evidence that its claim is uncertain. The Bank admitted that “[t]he SBA was reluctant to pay on its guaranty because the Bank was missing certain records relating to the Note.” On July 17, 1996, the SBA notified the Bank that it planned to “delay any purchase until an agreement is reached as to the amount owing on th[e] account that can be legally proved.” However, “[t]he SBA ultimately declined to honor its guaranty on the Note, in part because of the wide variance between the Bank’s and the Scotts’ amortization schedules.” The SBA terminated its guaranty entirely in December, 1997, “due to the Bank’s and the Scotts’ failure to come to an agreement regarding the Note’s outstanding balance.”
[¶ 60.] These deficiencies in the Bank’s own showing more than adequately demonstrate that the Bank failed to establish the absence of disputed issues of material fact and its right to $109,948.79 plus interest. The inconsistencies and uncertainties in the Bank’s own records certainly refute this Court’s appellate finding that “[t]he note ultimately matured on August 21, 1995, with an unpaid balance of $109,948.79 according to Bank’s records.” See swpra ¶ 8 (emphasis added).
[¶ 61.] It must finally be noted that the deficiencies in the Bank’s own showing are not the only evidence raising disputes of material fact. The Scotts raised other alleged errors in the Bank’s amortization schedule, including: (1) an alleged failure to give proper credit for a $38,000 equipment sale; (2) an alleged failure to credit any portion of the 1989 payments to principal reduction; and, (3) a Bank letter indicating the loan was current. Although the Bank has submitted “explanations” for these points, the Bank’s explanations and the Scotts’ assertions should both be resolved by a fact finder rather than by concluding that they raise no dispute of fact.
Summaries
[¶ 62.] I also dissent because I disagree with the Court’s evidentiary analysis of summaries. The summary at issue was Scotts’ amortization schedule, which was prepared by their certified public accountant, Kyle Repp. Although the Court correctly observes that this schedule could establish the defense of payment and create a dispute of material fact, see supra ¶ 25, the court incorrectly excludes the schedule from consideration. It does so because the Court concludes that it is a “summary” that is inadmissible under SDCL 19-18-6, Fed R Evid 1006. The Court concludes it inadmissible because the documents from which the “summary” was created no longer exist. The Court reasons that: (1) Scotts failed to establish their burden of proving the loss or destruction of records supporting such “secondary evidence,” and (2) Scotts failed to establish a foundation for it. See supra ¶¶ 26-31.
[¶ 63.] I dissent from the Court’s analysis because the amortization was not a summary; i.e. secondary evidence of the underlying documents. On the contrary, *662the Court concedes that “this amortization was not a summary” within the meaning of Rule 1006. See supra ¶¶ 32-33.
[¶ 64.] Summaries are admissible under Rule 1006 because “[t]he contents of voluminous writings, recordings, or photographs which cannot conveniently be examined in court may be presented in the form of a chart, summary, or calculation.” SDCL 19-18-6 (Rule 1006) (emphasis added). However, the Scotts did not offer their amortization schedule to prove the contents of the underlying records used to arrive at the amortization. The amortization was simply used to illustrate Repp’s reconstruction of the payments made in his deposition. Moreover, Repp’s amortization was the same kind of opinion that the Bank submitted through its amortization (which was also constructed despite lost or destroyed records).
[¶ 65.] These types of expert opinions are not covered by Rule 1006. “[N]ot all expert testimony that is seemingly summary in form falls within the parameters of Rule 1006. Opinion evidence, even if based upon review of voluminous data, remains opinion evidence ... and it need not satisfy Rule 1006.” 2 Gregory P. Joseph Stephen A. Salzburg, Evidence in America: The Federal Rules In the States, ch 70, 3 (1987). Therefore, the Court incorrectly analyzes the admissibility of Repp’s opinion under Rule 1006. Because the Scotts’ amortization was not offered as a summary (secondary evidence) of the underlying records, and because it was simply an opinion of the Scotts’ certified public accountant, it was not excluded from consideration by Rule 1006.
Opinion Evidence
[¶ 66.] The Court finally errors by concluding that Repp’s deposition testimony fails to qualify for consideration as expert opinion under SDCL 19-15-2 (Fed R Evid 702). First, the court’s conclusion is not supported by any analysis. See supra 34. More importantly, SDCL 19-15-3 (Fed R Evid 703) only requires that such expert opinions be based upon “facts or data ... perceived or made known [to the expert] at or before the hearing.” Moreover, if the underlying records are “of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence.” Id.
[¶ 67.] Here, the Scott’s certified public accountant of over twenty years constructed the amortization from the Scotts’ year-end bank records, income tax returns and IRS 1099s. Significantly, Bank does not, nor could it claim that accountants do not reasonably and customarily rely upon such records for such purposes. Under those circumstances, Scotts’ amortization was just as usable for summary judgment purposes as the Bank’s amortization.16 Both amortizations were opinion evidence based upon each party’s different factual assumptions. The difference in factual assumptions clearly raised a disputed issue of material fact concerning the calculation of principal remaining due on the note.
[¶ 68.] For these reasons, summary judgment was incorrectly entered. The disputes concerning the amount of principal due on the note should be determined at a trial.
[¶ 69.] GILBERTSON, Chief Justice, joins Justice Zinter’s dissent.
. Repp testified at his deposition that the underlying tax records were destroyed pursuant to his accounting office's old records policy-
. Although Repp did not have current access to all of the underlying records, neither did the Bank.