Data that is lost due to the age or neglect of the medium on which it is stored.
Examples of this are paper storage such as paper tape or punched cards which may get mold, mildewe, ripped or poorly stored so they can not be read again. They may also become so old that there is no longer any equipment in working order to read them.
See also Bit Rot, Crufty, Developer's Optimism, Kluge and Toy Code.
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