Curiously, the apex of lost media is in our own era. The problem cannot get worse than it is. The irony is that this is an era where unprecedented technological revolutions are taking place, and yet we're losing important information. This has to be as tragic as the burning of the Great Library of Alexandria around 47 BC.
Our technology industry comes out with formats faster than anyone can use them. These peripheral formats, with their data, very easily can get lost. Eight tracks, minidiscs, and digital audio tapes come to mind in the music industry. Betamax comes to mind for the video industry. Computer file formats are also at risk. Who has a copy of XyWrite around to open that old word processing file? Not to mention the old 5 1/4" floppy discs, or Jazz discs. So what's the solution? Keep shuffling our data from one disc format to the next, staying one step ahead of what is out of date. Maybe the Egyptians had it right after all. Save it one paper, I doubt we'll be able to read today's discs and cartridges 20 years from now, let alone 2000 years from now.