Hi, on boxrec Joe Louis' record is 66-3, however I have seen his record as being 68-3 and also 69-3 previously on boxrec.
Please look at his record at the following link and you will find that his record was 68-3. Also, if you look under the year 1944 you will see that Louis had a fight vs a guy called Johnny Davis that was sanctioned as being a defence of his world title but for some reason ppl class it as an exhibition. If the New York commission sanctioned it then surely it counts? So his record was 69-3 with (55 ko's) and 26 title defences.
http://www.cyberboxingzone.com/boxing/jlouis.htm
Please let me know your findings.