I found this article on piracy on Asahi.com:
The magicom devices, which are spreading rapidly overseas, typically comprise of a cartridge about the same size as an authentic game disk and a separate memory card used to store downloaded software. Alternatively, some pirates modify the game consoles themselves.
The objective is to make hardware capable of circumventing the anti-piracy systems of the game makers.
Nintendo Co. said magicom hardware was largely to blame for a nearly 50-percent drop in sales in Europe in recent months.
Globally, the company estimates that annual losses are in the region of trillions of yen.
I wish I could see how they collected their data.
My first objection was that I don't see how half of Nintendo's customers could all have bought the same piracy cartridge. But then I realized that it wasn't half the customers, but half the market. Even so, I still don't see how it's possible. I don't think very many people have the technical skills or the inclination. Besides, aren't we in the middle of a recession? I'd say that it's more likely that people aren't buying because they simply don't have the money.
There's also this fact about music pirates that may apply here. Did you know that the biggest music pirates also buy the most music? Since piracy has been shown to have a positive effect on music, I'd say that the same principle probably applies to video games.
Do you want to know the most obvious problem with this claim? How exactly do you get market data on people who aren't in the market? I can think of a few ways, actually: surveys, report-home-apps, and spyware. But until I see how the data was gathered, I don't trust it.