What is the difference between past and future loss of earning capacity?

Both past and future loss of earning capacity address the same loss. However, there are differences in how this loss is assessed before trial and after trial. To the extent past loss of capacity relies on facts which are capable of proof, those facts must be proven on the balance of probabilities. To the extent past loss of capacity relies on hypothetical facts, the court must be satisfied that there is a real and substantial possibility of such facts occurring. The court may assess the likelihood of such hypothetical facts occurring, and discount or increase an award to reflect such contingencies. Future losses are almost always based on hypothetical facts, and are assessed on the standard of real and substantial possibility with consideration of relevant contingencies: Rousta v. MacKay, 2018 BCCA 29 at para. 14.

In determining loss of capacity, the court must first determine if there is a loss of capacity. If there is a loss of capacity, the court must determine whether the loss of capacity will result in a pecuniary loss. A likelihood of a pecuniary loss must be valued by the court, grounded in the evidence, and the court must assess the relative likelihood of the possibility of such loss occurring: Rab v. Prescott, 2021 BCCA 345 at para. 47.