Both sides inflated their figures, either by accident or design. A common tactic was for 2 pilots to agree to back up each others claim for a kill.

I can't remember if I mentioned it in this thread, or another, but Hans-Joachim Marseille, who claimed 17 RAF kills in one day over the desert. RAF records show that they didn't lose a single plane that day.......

EA, to answer your question, so (comparitively) rare were the shootings down of Luftwaffe planes in 44-45 that historians can go through the records and not only verify RAF/USAAF kills, but actually name with some certainty the crews shot down.