Scope of moving image loss

From our class discussion tonight – a few people mentioned moving images – the attached article, “The Gap Between 1 and 0: Digital Video and the Omissions of Film History,” explains the extent of how many films have already been lost.  For instance, “Of all films produced worldwide during the silent era before 1930, approximately ninety percent have been lost.”  This particular article does not address digital preservation but thought people would be interested in the scope of the loss already in just analog.  And from analog to DVD.