In progress NPD predicting tool

[Megiddo]

Bofferbrauer2 said:

Besides, from yesterday to today the consoles would have dropped a grand total of 3 spots on Gamestop. That just doesn't work with your theory and calculation as some items dropped more despite still selling.

It does when you understand that a rolling period doesn't just take into effect one day's sales. Some of those that fell more did so because they had sold a lot at the tail end of the rolling period so when that day's numbers were dropped from the rolling period in consideration it in turn dropped in the rankings.