Whats the usual increase in sales % during the holidays?

[ssj12]

Figure these are console sales

DS: 3 million
PSP: 1.2 million
Wii: 7 million
PS3: 5 million
360: 2 million
PS2: 2 million

And now PC sales

PC: 17 million



I know we cant track PC sales but I figure that might be to low.