This issue was recently dealt with by the Supreme Court of British Columbia:
Here, a part time accountant, who had plans to expand her business into a full time practice, was injured in a motor vehicle accident. As a result of the injuries she sustained in this accident, she was unable to expand her accounting practice. She was, however, successfully able to prove her case in court.
Currently,the plaintiff had to prove that, if they had not been injured, they would have had a real and substantial chance of expanding their business. The “real and substantial” legal test is dealt with in more depth in the case of Perren v. Lalari:
Basically, what this legal test boils down to is whether you can convince the judge there was an actual chance of you losing income and not merely just “speculation”. The best way to do this is to provide evidence. Evidence can be many different things. In the above case involving the accountant, the plaintiff’s credibility was probably the main factor. The Plaintiff was an accountant and the judge believed that she would have expanded her business, if she had been healthy.
In more speculative cases, such as a young person who has not yet entered the legal market, things become more speculative. That does not mean, however, that they are barred from making a legal claim. The judge will look at factors like academic performance, what schools/programs have they applied to, what did their parents do for work, etc..
In cases where things are very speculative, it is especially important to hire a lawyer, in order to ensure your case is properly framed.