What is the test for determining whether a hypothetical event is a real or substantial possibility?

"Hypothetical events [and] future events need not be proven on a balance of probabilities. Instead they are simply given weight according to their relative likelihood.": Athey v. Leonati, 1996 CanLII 183 (SCC), [1996] S.C.J. 102, para. 27. Consequently, "A future or hypothetical possibility will be taken into consideration as long as it is a real and substantial possibility and not mere speculation" (also, para. 27).

This leads to an approach under which the judge makes findings about what the victim would have earned before trial without injury and projects incomes in the future, both hypothetical income without the injury and projected income with it, on the basis of real and substantial possibilities. This often involves the application of contingencies. See Justice Oland discussion in Kern v. Steele, 2003 NSCA 147 at para. 56 to para. 66 and Justice Saunders' commentary at para. 101 and 102 of MacIsaac v. Deveaux, 2004 NSCA 87.