How accurate is VGChartz when it comes to small sales data?

[Mr.Playstation]

MarkNL said:
Hi, my first post so short introduction:
Mark from Holland, near The Hague. PS1 and PS2 collector, RPG game player and student Informatics. Came across this site while searching for the sales numbers for some PS2 games. So, that leads directly to a few questions I have. Probably some of you are able to answer them.

So, what is the source of all this information? I'm mainly interested in the sales numbers from the PS2 era.
I know it's very difficult, but let's take an example I stumbled across: VGZChart says there are about 0.02M (like 20.000) copies of Valkyrie Profile 2 sold in Europe. When I open the financial report of Square Enix, I see there are at least 170.000 sold in one year. That's a pretty reliable source if you ask me. Where does this very big difference comes from?

Second question: is there a way to get the sales amounts myself? Is it the effort of mailing companies worth?

Thanks in advance,
Mark

Hey welcome to VGChartz Mark, sorry for the late reply.

So the source of all of these numbers ( even PS2 numbers ) come from ioi, who makes a sort of educated guess on how much each game has sold and then usually fixes them ounce more accurate sources are revealed for those sources. I wouldn't really hold this place as very accurate on PS2 sales as this site started out in 2005 the beginning of gen 7 so much of the info for gen 6 and under is incorrect.

About question 2, I don't think it would be worth it to get sales numbers yourself. I suggest you contact ioi ( find his profile ) and sending him a pm about what you want to do and he can give you some advice.