Keep in mind, unlike Amazon, other online retailers don't update by hour or have total monthly sales. From what i noticed they update every day.
For gamestop you should use the console filter to make it easier
I think you can do the same for Walmart and Target.
Yeah, I am sure there are differences in the way those lists are made. The idea is to have a trial and errors approach for a few month and see if we can make something of this.
I am going to update daily for now and will adjust if needed.
Console filter makes things easier indeed but is not compatible with the point system (at least, as it is now !). Gamestop list is kind of a problem though, as very few consoles are in the top 100.