Claims,claims,claims.
Here's a quote from someone who understood what they were.
"The experience of two wars shows that in large-scale offensive operations the claims to the destruction of enemy aircraft made by pilots, however honestly made and carefully scrutinized, are a most inaccurate guide to the true situation. Moreover, the results achieved by an offensive can rarely be judged by a mere statistical comparison of casualties suffered and inflicted. Except when an operation has been launched purely for the purpose of procuring the attrition of the opposing force, a broader view than this must be taken of the strategic purpose and the extent to which it has been achieved."
From a report submitted on 29th February,1948,by Marshal of the Royal Air Force Sir Sholto Douglas, G.C.B., M.C., D.F.C. the former Commander-in-Chief of Fighter Command, Royal Air Force.