How Long Is Long-Term Data Storage?

In the context of archiving of physical documents, long-term storage has long been accepted to mean centuries. Digital documents are much more ephemeral, so archivists should be aware of the inherent limitations of the technologies available for preservation of digital data. This paper compiles the results of several studies on this subject, in addition to presenting new findings on what can be expected for recordable optical discs (CDs and DVDs). The bottom line is that, with one notable exception, digital data cannot be expected to endure using any existing technologies.