Only 20% of software in US pirated, lowest % in the world.

[ChichiriMuyo]

http://www.reuters.com/article/technologyNews/idUSTRE54B0UD20090512

This is, of course, for all software.  Not just games.  However, I figured it'd be relevant to the interests of people who frequent vgchartz.

Of course it also has the highest software sales in the world by far, so it makes up the highest amount of "lost" revenues.  On the flipside, only 20% of software sold in China is legit and it's not even in the top 7 pirating nations.