[Doug Stankey]

For the period of the air attacks against Britain, your best bet for finding loss data is to obtain or borrow copies of:

Ramsey, Winston (Ed.). The Blitz, Then And Now; Vol.1, 2 and 3 (London: Battle of Britain Prints International, Ltd., 1988).

These are expensive but very good and contain detailed loss info. For KG 53, it would be good for the period July 1940 to May 1941. Beyond that, the only resort is to get the microfilms of the actual loss reports from the Bundesarchiv in Freiburg:

BA-MA Freiburg RL 2 III Gen.Qu. (6.Abt.) Meldungen über Flugzeugunfälle und Verluste ... (LRs – Loss Reports).

These are expensive and somewhat hard to read. They are also incomplete. Beyond that there are only incidental references scattered over many books