From this source, on NT textual criticism, itself well worth reading, I learn of two databases which are worth a look.
The Pinakes database (http://pinakes.irht.cnrs.fr/) aims to bring together catalogue entries for all manuscripts of Greek texts predating the sixteenth century, supplementing the
Leuven Database of Ancient Books (LDAB, http://www.trismegistos.org/ldab/).
The latter gave some interesting results. Who would have imagined that we have a 4th century fragment of the Church History of Eusebius?
Even better Trismegistos often provides link to digital editions or metadata of/on ancient papyrii in greek, latin, coptic, syriac and other languages !
Mmm. Now that I had not seen! I must search some more!
LDAB is a basically a list of literary papyri plus manuscripts from that era. By dividing number of books on LDAB with number of papyri published (another number at Trsimegistos), you get a good idea of the percentage of literary papyri as part of all the papyri
Very interesting — thank you!