Gamasutra reports that Japan's Computer Entertainment Suppliers Association conducted a study to estimate the total amount of money lost to piracy on portable game consoles
. The figure they arrived at? $41.5 billion from 2004 to 2009. Quoting:
"CESA checked the download counts for the top 20 Japanese games at what it considers the top 114 piracy sites, recording those figures from 2004 to 2009. After calculating the total for handheld piracy in Japan with that method, the groups multiplied that number by four to reach the worldwide amount, presuming that Japan makes up 25 percent of the world's software market. CESA and Baba Lab did not take into account other popular distribution methods for pirated games like peer-to-peer sharing, so the groups admit that the actual figures for DS and PSP software piracy could be much higher than the ¥3.816 trillion amount the study found."