Currently, blocklist.de has the following Stats/User:
Daily Mails: ~280499
Web-Traffic: ~58 GB
RBL-/API-Traffic: ~210 GB
Mail (In/Out)-Traffic: ~29 GB
Traffic over IPv6 (Mail, Web..): ~2GB
To this data, there comes 1,5TB Traffic between the Web-/Mail-Server and the MySQL-Server. The MySQL-Server sends over 4.1 GB each Hour out.