NPD Says PC Retail Down 50%

Talking at D.I.C.E., Anita Frazier of the NPD Group noted that the PC retail market is down 50%, before saying they'd estimate that 50% retail has been filled by the digital market.
Speaking at the DICE Summit in Las Vegas today, Anita Frazier of the NPD Group has revealed an interesting little piece of information regarding the PC market, saying retail sales are down by over 50%.

That's over the past seven years. Grim reading, then? Not really. Although NPD "has been having trouble with is digital downloads" tracking, Frazier was able to announce that, as a rough estimate, the PC gaming market is "at least twice what retail shows".
There is more info on digital download from Frazier here.