Dark data is all the information companies store but never use—sometimes 60-80%...

https://www.animenewsnetwork.com/bbs/phpBB2/profile.php?mode=viewprofile&u=1221209

Dark data is all the information companies store but never use—sometimes 60-80% of it. This hidden data adds up, wasting around $2.5 million a year on storage and management