PC Data was an American market research and point of sale tracking firm founded in 1991 and based in Reston, Virginia.
Initially, the firm tracked only the United States' computer software market,[1] but later expanded to include hardware sales and, in 1999, Internet traffic.
[1][2] By 1996, The Washington Post described PC Data as "the preeminent tabulator of facts and figures of the monthly sales of consumer software in the United States".
[3] In March 2001, The NPD Group purchased PC Data's point-of-sale research branch and merged it with its Intelect Market Tracking division.
[4][5] Following a legal settlement with the rival company Jupiter Media Matrix regarding patent infringement, PC Data ceased Internet traffic research and closed later in March.