I think considering Asian markets like China, that figure is possibly near the truth. But then again, those markets would never pay $50 for a PC game anyway. For them, they need a different strategy. Realistically speaking, actual piracy rate -- i.e. people who would buy the game if they had absolutely no way to pirate it -- is probably a lot lower.
That being said, I am sure a lot has to do with Ubisoft being the most hated name in the PC games business. This is the first time a PC game publisher is bemoaning PC piracy, and I have no sympathy for them at all.