On the Reliability of Software Piracy Statistics

Based on a review of the methodology and empirical analysis of software piracy statistics compiled by the Business Software Alliance (BSA), I conclude that a change in the BSA consultant and methodology around 2002-03 had systematic effects on published piracy rates. The trend rate of decrease of piracy rates fell from 2.0% points per year to 1.1% points per year. Among countries for which the BSA´s piracy statistics depended on a projection of software usage, the trend decrease in the piracy rate was under-estimated and the sensitivity of piracy to changes in income was over-estimated. Any government pronouncement or action, and academic study using the BSA software piracy statistics should take account of changes in the BSA consultant and methodology.