I am wondering if your question is regarding not necessarily guilt, but possible restitution, which in any US jurisdiction of which I am aware, would be the only criminal context where this question would have relevance. And in that case, most US courts would probably only award as restitution those direct and documented costs (i.e. medical bills, possible lost work or other expenses) that exist at the time of sentencing.
If your question is more about civil damages in a tort lawsuit, future losses become much more relevant. A successful argument for awarding more damages for a particular loss would likely require expert testimony.
Edit: regarding Andrew's suggestion, see North Carolina's statute on criminal restitution, N.C.G.S. 15A-1340.34 and following