I doubt it. I remember following up with some people a few years ago about how useful DFC Intelligence was and was it worth buying. I got back the response that it could be no more than educated guesses and gathering of press releases etc to get this information because no-one really has any proper data on hardware sales and in particular online sales. So the 11Billion I would take to be an extrapolation. I may be wrong of course.
Personally I think you will find that most of the PC market is subscriptions to mmo’s and the casual games market as found by bored people browsing the web – so hardware is whatever average pc happens to be in the lounge.