I need to know the probability of having a checked luggage lost on a direct (no connection) flight with AF (more specifically LAX-CDG). Is that info available somewhere?

By "lost", I mean really lost, not delayed by a few days.

The reason why I'm asking this is that I have to rappatriate from the US a piece of unique scientific equipment (with no commercial value however), too large to be a carry-on, and I'd like to investigate the risk associated with the different options before making a decision.