What is the test for assessing the quantum of capital loss for the purposes of a widow's claim?

In Keizer v. Hanna, 1978 CanLII 28 (SCC), [1978] 2 S.C.R. 342, Dickson J. said the following at 351-52: … The appellant is entitled to an award of such amount as will assure her the comforts and station in life which she would have enjoyed but for the untimely death of her husband. If one is speaking of contingencies, I think it is not unreasonable to give primary attention to the contingencies, and they are many, the occurrence of which would result in making the award, in the light of events, entirely inadequate. An assessment must be neither punitive nor influenced by sentimentality. It is largely an exercise of business judgment. The question is whether a stated amount of capital will provide, during the period in question, having regard to contingencies tending to increase or decrease the award, a monthly sum at least equal to that which might reasonably have been expected during the continued life of the deceased.