There are a number of entries in the Pitching table that have invalid 0 entries in the BFP field, where it's fairly clear that the actual value is unknown and
I don't yet have such a dataset (although I plan to in the future). You might try posting an inquiry in the Negro Leagues Yahoo Group to see if someone
... There is no "official" way, is there? The convention is whatever it is. In some sports, they simply show whoever has the most "points", pts% be damned.