"Monopoly corrupts. Absolute monopoly corrupts absolutely."
  According to the RIAA, the value of all CD's, live presentations, music videos, dvds in 1998 (from http://www.riaa.com/pdf/md_riaa10yr.pdf) was 13.72 billion US$.

According to the SOI, in 1998 the business receipts of the computer and electronic product manufacturing including both hardware and software (they do not divide it further) was 560.27 billion US$. This of course excludes the value of all the data stored on computers.
 

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