To be precise, the figures below are for the industry designated by the Census Bureau as Prerecorded Tape, Compact Disc and Record Stores [NAICS 45-1220]. Now, the very name of this industry will likely explain why it has seen such precipitous declines over the last decade… since music is now so often purchased online and downloaded as an electronic file. It also serves as an extreme example of a retailing segment that is having to grapple with a major shift in how business is done.

Geographic reference: United States
Year: 1997 and 2007
Market size: Number of Establishments: 8,158 and 4,102 respectively.
Market size: Sales: $7.37 and $3.51 billion respectively.
Market size: Employment: 66,623 and 28,685 respectively.
Source: “Sector 44: EC0744I2: Retail Trade: Industry Series: Preliminary Comparative Statistics for the United States (2002 NAICS Basis): 2007 and 2002,” 2007 Economic Census, available online here. The data from 1997 are from the 1997 Economic Census, after conversion of the data to a NAICS 2002 basis.
Original source: U.S. Department of Commerce, Bureau of the Census.