And 49% of files have not been accessed in more than a year, according to survey.
Two-thirds of data stored on primary storage systems has not been accessed in more than six months, according to a survey.
NTP Software claims its research suggests this trend is evidence of inefficient storage use, which creates ongoing cost expenditures and potential compliance issues.
NTP said its storage assessment scanned about half a billion files totalling over 300tb of customers’ data across several storage environments.
It revealed that 49% of files have not been accessed in more than a year and one third of storage is consumed by less than 0.1% of files.
Other findings of the survey include 19.1% of data is consumed by duplicate files and there were over 14m files with zero file size and about 900,000 empty directories.
The survey found that deploying a tiering solution can reduce costs and increase system speed, while archiving stale files will decrease file and directory density and increase hard disk performance.
NTP Software CEO Bruce Backa said: "It’s staggering to see just how many stale, duplicate and empty files are being kept on expensive primary storage by organisations of every size across a variety of industries.
"Files that have not been accessed in six months or more are prime archiving candidates."