Aj_habfan on 09 December 2009
I think it's that most people would see the vgchartz numbers and directly compare them to NPD, making it seem like vgchartz was off more then it was. The real issue is that vgchartz counts all of North America and South America with it's USA data, and NPD is JUST USA. So vgchartz adjusts their data to show only the USA sales for the month, making it more in line with NPD and helping avoid even more confusion.
