What is the proper assessment of loss of future earning capacity for a plaintiff?

There are two possible approaches to the assessment of loss of future earning capacity: the “earnings approach” and the “capital asset approach”. Both are correct. The earnings approach is generally more useful when the loss is easily measurable: Perren, at para. 32. When the loss “is not measurable in a pecuniary way”, the capital asset approach is more appropriate: Perren, at para. 12. The earnings approach involves a form of math-oriented methodology such as: i) postulating a minimum annual income loss for the plaintiff’s remaining years of work, multiplying the annual projected loss by the number of remaining years and calculating a present value; or ii) awarding the plaintiff’s entire annual income for a year or two: Gilbert v. Bottle, 2011 BCSC 1389 at para. 233 [Gilbert].