concurring in part and dissenting in part:
I am impelled to differ with the majority’s treatment of the 1983 assessment.
We deal here with a statutory command that property be assessed at market value and that, in determining such value, the decision-maker “shall take into account any factor which might have a bearing on the market value of the real property.” D.C.Code § 47-820(n) (1987 repl.) (emphasis added). What particular factors may af-*1085feet the market value of a particular piece of property and when they begin to exert that effect to an appreciable extent are basically questions of fact, determined with the input of those skilled in the field.
We are reviewing a grant of summary judgment. Although the record is not entirely clear, I read appellant as asserting that on the critical date in question, January 1,1982, the prospects of inclusion in an historic district were appreciably affecting the market value of its property. Although no application was formally filed until a month later, considerable activity toward historic district status was taking place. Satisfying though it is to draw bright lines in the law, I am unable to say that there could be no legitimate factual dispute about the effect of such activity on market value.
The majority quite rightly looks to zoning changes in eminent domain litigation for a close analogy. The leading authority on the subject summarizes the law as follows:
The potential exercise of the police power in such manner as to affect deleteriously the value of property cannot be presumed. However, where the likelihood of the future exercise of such power is so great as to have an observable effect upon present market value, it may be considered in determining the compensation to be paid for such property when it is taken by eminent domain.
4 Nichols on Eminent Domain § 12.322, at 12-627 (rev. 3d ed. 1985) (emphasis added). See also id. § 12.322[1], at 12-637. Likewise, in jurisprudence applicable to our decision-making, it has been held that “[o]nly if the trial judge is satisfied that a jury could not reasonably conclude that the possibility of a zoning change would affect the fair market value should he instruct the jury to disregard that element of value.” H & R Corp. v. District of Columbia, 122 U.S.App.D.C. 43, 45, 351 F.2d 740, 742 (1965); see also Reservation Eleven Assocs. v. District of Columbia, 136 U.S.App. D.C. 311, 313, 420 F.2d 153, 155 (1969).
In my view, the oft-mentioned requirement of “reasonable probability” or the like1 is a short-hand encapsulation of the concept that the prospect of change must be such as to exert an effect on market value.2 In any event, I certainly cannot say on the record before us that the filing of a historic district application is, as a matter of law, the critical event that turns the prospect of change into such a probability, even in the general run of cases. Furthermore, I do not read the statutory language that assessments shall be based upon the sources of information available to the Mayor as precluding the use of information about prospective historic district status that would be known generally to informed buyers. Assessors are not limited to information contained in formal records. D.C.Code § 47-820(a).
Accordingly, I would reverse in its entirety the order granting the summary judgment and remand for further proceedings.3
. As pointed out in H & R Corp. v. District of Columbia, supra, strictly speaking, the issue is not whether there is in fact a reasonable probability (the opinion indeed uses the phrase "reasonable possibility") but rather whether knowledgeable buyers would think there was a reasonable probability. 122 U.S.App.D.C. at 44 n. 1, 351 F.2d at 741 n. 1.
. The relationship between expressions of the immediacy of prospective change and actual effect on market value is insightfully discussed in Ada County Highway District v. Magwire, 104 Idaho 656, 662 P.2d 237 (1983), citing cases. See 4 Nichols on Eminent Domain, supra, § 12.322(1), at 12-651, -653 ("even where the likelihood of the change is remote, if the likelihood is sufficient to have an appreciably enhancing effect upon present market value, it may be considered").
.I might add that the District’s assertion that true comparables (perhaps brought about by adjustment) would reflect the market’s assessment of the likelihood of historic district status seems quite compelling. Whether those offered by the District are in reality such is another factual question I understand to be in dispute, and not one I would resolve on this appeal.