Unfortunately I don't think you can, because this study is so different in its scope and its approach, and in the Ipsos-Oxford Economics methodology, but here are numbers that I think we can't ignore: isoHunt has 40,000,000 peers and 6,000,000 torrents. Those are kinds of numbers that I think speak for themselves, in terms of the kind of impact this has on an industry like ours.
On February 17th, 2011. See this statement in context.