joined by RABI-NO WITZ, Justice, dissenting.
Subsection 3 of AS 23.30.220 authorizes the Workers’ Compensation Board to calculate average weekly wage in accordance with the usual wage for similar services rendered under similar circumstances if the Board determines that the average weekly *567wage at the time of injury “cannot be fairly calculated under” the mathematical formula of subsection 2. By what test is the concept of fairness expressed in subsection 3 to be measured? The objective in calculating average weekly wage is to produce an honest approximation of the claimant’s probable future earning capacity during the period in which compensation is to be paid. Thus, if the mathematical formula of subsection 2 does yield an honest approximation of probable future earnings it can be considered fair; if it does not it cannot be considered fair. As Larson puts it:
The entire objective of wage calculation is to arrive at a fair approximation of claimant’s probable future earning capacity. His disability reaches into the future, not the past; his loss as a result of injury must be thought of in terms of the impact on probable future earnings, perhaps for the rest of his life. This may sound like belaboring the obvious; but unless the elementary guiding principle is kept constantly in mind while dealing with wage calculation, there may be a temptation to lapse into the fallacy of supposing that compensation theory is necessarily satisfied when a mechanical representation of this claimant’s own earnings in some arbitrary past period has been used as a wage basis.
2 A. Larson, The Law of Workmen’s Compensation § 60.11(d), at 10-564 (1981).
In the present case the Board has made a factual finding that the average weekly wage for Ms. Dupree at the time she was injured cannot be fairly calculated under subsection 2. This factual finding is certainly supported by substantial evidence given the major discrepancy between Du-pree’s earnings in her steady full-time job at the time of injury, in contrast to her earnings in her short term job associated with the construction of the Trans-Alaska Pipeline. During 1976 when she worked on the pipeline she made, on the average, $538.00 per week. When she was injured in 1978 while working for the state her gross wages were approximately $300.00 per week. Dupree testified that she had worked for the state as a secretary for nine years before working on the pipeline, that she returned to the state payroll after pipeline construction had terminated, and that when she was injured her intent was to continue to work for the state indefinitely.1 There was no contrary evidence. The Board in making the factual finding of unfairness has done exactly what subsection 3 of the statute has directed it to do. Since the finding is supported by substantial evidence we cannot properly interfere with it. Thus, the decision of the Board must be affirmed.
Today’s majority opinion, however, if I read it correctly, does not take issue with the factual determination that Dupree’s average weekly wage at the time she was injured could not fairly be calculated under the mathematical formula supplied by subsection 2. Instead, the opinion holds that “fairly” as that term is used in subsection 3 cannot be taken literally. Instead, its meaning must be restricted to cases where there is a record “establishing a claimant’s absolute inability to match past earnings . . .. ” (At 566, n. 8) I am not sure that I know what this language means.
Philosophically one may doubt that an absolute inability can ever exist, for there is a remote possibility of nearly anything. More reasonably, perhaps the majority merely intends to say that the concept of unfairness as expressed in subsection 3 means obvious or clear unfairness. While I would not join in this construction of the statute, because it is not what the statute says, it is true that the triggering finding of unfairness under subsection 3 cannot be made merely because there is a slight variance between wages at the time of injury and the average weekly wage arrived at under the formula of subsection 2.2 A *568slight variance does not result in unfairness. A significant variance results in unfairness. Perhaps the majority would say that a large variance produces an obvious unfairness.
I believe that the Legislature has authorized the Board to abandon the formula of subsection 2 where there is a significant difference between the average weekly wage so calculated and the actual wage. The majority, again if I read the opinion correctly, believes that the Board can act when the variance is more than significant, either large, or very large. If that is what the majority means, however, the question that it should take up is whether a sufficiently large variance exists in this case. The difference between the average weekly wage calculated under subsection 2, $538.00, and the actual weekly wage, $300.00, is $238.00, a sum that is more than two-thirds of the actual wage. To me, this difference seems both significant and large enough to result in obvious unfairness. The majority opinion should at least explain why this is not so.
Finally, the majority opinion suggests that reading subsection 3 literally will increase uncertainty and therefore litigation. It is true that if subsection 3 were not in the statute there would be a higher measure of certainty in calculating average weekly wage. However, unfortunately for the cause of certainty but, as the Legislature must have thought, fortunately for the cause of fairness, subsection 3 does exist and it is our task to apply it sensibly. “It is always harder work to apply tests of reasonableness than to apply self-executing mathematical tests. But the former cannot be avoided in a mature and civilized legal system.” 2 A. Larson, supra, at 10-557.
. In Vetter v. Alaska Workmen’s Compensation Board, 524 P.2d 264, 266 (Alaska 1974), we noted that the claimant’s intentions as to employment in the future were relevant to a determination of future earning capacity.
. As Larson puts it:
*568The mere fact that the application of the first test, based on claimant’s own earnings record, may produce an annual wage slightly less than the actual wage is not reason enough for abandoning it as unreasonable.
2 A. Larson, supra, at 10-555.