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

https://www.bright-bookmarks.win/dark-data-is-the-information-your-organization-collects-but-doesn-t-use-often

Dark data is all the information companies collect but never use—often 60-80% of their stored data. This inactive data costs businesses an average of $2.5 million a year in storage and management expenses