This case arises from an appeal to the Superior Court from a decision of the board of tax review of the city of Norwalk increasing the assessment on a building located at 25 Van Zant Street in that city. The plaintiffs are the owners of units of the 25 Van Zant Street condominium. The subject building was one of the first commercial condominium conversions in the state of Connecticut. The premises were converted from a multi-tenanted factory to an industrial condominium.
On February 14, 15, and 19, 1980, the defendant board of tax review reassessed the value of the condominium according to the defendant tax assessor’s revaluation, even though a reassessment of the same premises had been done in 1973. The 1980 reassessment was done as a supplement to the 1979 grand list. The assessor’s revaluation nearly quadrupled the property value of the condominium from the time of the 1973 valuation.
The plaintiffs appealed the board’s actions affecting the 1979 tax list to the Superior Court. Thereafter, pursuant to General Statutes § 12-118,1 the plaintiffs *754amended their appeal to include the subsequent tax list years 1980,1981 and 1982. On November 18,1982, the trial court granted a motion for summary judgment in favor of the plaintiffs as to the 1979 grand list only. The court held that certain defects in the notice given to the plaintiffs with respect to the 1979 list year mandated the granting of the summary judgment.
Pursuant to the court’s memorandum of decision on the motion for summary judgment, the plaintiffs’ counsel prepared a judgment file based on the trial court’s decision. The memorandum of decision made no mention of an award of interest, but the judgment file prepared by plaintiffs’ counsel and subsequently signed by the court, Nigro, J., stated that the sums owed to the plaintiffs were to be “repaid with statutory interest.”
Thereafter, on July 23,1986, the parties executed a stipulation for judgment before the court, Emmett, J., *755which was entered as a judgment on July 31,1986. The stipulation provided for rebates of tax overpayments and postjudgment interest and pertained to the 1980, 1981 and 1982 list years only. The 1979 list year had been disposed of by virtue of the summary judgment. The parties fully complied with the stipulation.
The defendant contends that the stipulation between the parties dated July 31,1986, fully covered and settled all matters contained within the plaintiffs’ complaint, including the consideration of all interest. The plaintiffs argue that the stipulation was silent as to prejudgment interest for the 1979 list year, and that such silence was at variance with the judgment file of November 30,1982, which the plaintiffs contend only could have referred to prejudgment interest.
On January 30,1987, the trial court, Ryan, J., summarily denied the plaintiffs’ motion for execution seeking an order from the court permitting them to execute upon the summary judgment for prejudgment interest as to the 1979 list year. Specifically, the plaintiffs sought to execute the judgment in order to collect prejudgment interest on the tax overpayments from the date on which they paid the taxes until the date of the summary judgment. The plaintiffs contend that they should at least have been given the opportunity for a hearing on the ambiguity between the judgment file and the stipulation during consideration of their motion for execution, but were precluded from doing so by the trial court. The trial court’s denial of the plaintiffs’ motion for execution of judgment is the subject of the present appeal.
The trial court issued no written memorandum of decision for this court’s review, but orally stated on the record the basis for its order. Neither party moved for an articulation of the court’s decision. Under these circumstances, we limit our review to a determination of *756whether, in light of the entire record before us, the trial court’s decision was erroneous as a matter of law. Practice Book § 4061.
We first note that the court’s grant of summary judgment was entered pursuant to General Statutes § 12-1192 which provides for the reimbursement of the overpaid taxes in accordance with the judgment of the Superior Court. General Statutes § 12-119 also provides that the trial court may make a discretionary award of interest. In its memorandum of decision, the first trial court did not address the matter of interest, but “directed [the plaintiffs’ counsel] to submit a form of judgment” which would conform to the court’s memorandum. The judgment subsequently prepared by the plaintiffs’ counsel, signed by the court, and dated November 30, 1982, specified that the tax overpayments be repaid to the plaintiffs “with statutory interest.” No appeal was taken from that judgment.
*757It is well established that the judgment file itself and not the court’s memorandum of decision constitutes the record judgment. Pepin v. Danbury, 171 Conn. 74, 81, 368 A.2d 88 (1976); Harris v. First National Bank & Trust Co., 139 Conn. 749, 752, 97 A.2d 260 (1953). A claimed discrepancy between the memorandum of decision and the judgment file is one of substance and should have been raised by an appeal from the judgment. Ravizza v. Waldie, 3 Conn. App. 491, 494, 490 A.2d 90 (1985). An instrument signed by a judge rendering a judgment is prima facie the judgment of the court, and is evidence of what the court has decided. 46 Am. Jur., Judgments § 70; see also Practice Book § 338. Accordingly, we find that the first trial court exercised its discretion and awarded the plaintiff interest on the judgment.
General Statutes § 52-5983 provides that an execution may issue upon a judgment for money damages for up to twenty years from the date the judgment entered. In this case, there is no real dispute that the summary judgment rendered by the trial court was for money damages. From our review of the record,4 how*758ever, it is apparent that the trial court, while considering the plaintiffs’ motion for execution on March 2, 1987, ruled that it would not allow interest on the judg*759ment solely because it had been entered some five years earlier. This ruling was clearly erroneous because, as we noted above, execution could issue upon the judgment for up to twenty years. In refusing to execute upon the judgment because it considered the judgment stale, the trial court did not rule upon the questions of whether the stipulated judgment entered into by the parties covered the 1979 tax year or whether the summary judgment included prejudgment interest for the 1979 tax year. Accordingly, this case must be remanded for a resolution of those questions.
There is error, the decision of the trial court is set aside and the case is remanded for a rehearing on the plaintiffs’ motion for execution.
In this opinion the other judges concurred.