From BBC News:
In fact, it turns out that images stored electronically just 15 years ago are already becoming difficult to access. The Domesday Project, a multimedia archive of British life in 1986 designed as a digital counterpart to the original Domesday Book compiled by monks in 1086, was stored on laser discs.
The equipment needed to view the images on these discs is already very rare, yet the Domesday book, written on paper, is still accessible more than 1,000 years after it was produced.