Weighted Averages explanation

Hi all,

I have an issue as describes in the file regarding weighted averages. I have a sales where my averages value per sale in product A, B, C is fixed the coming years (only volume changes) - but my overall average value per sale seem to change. Hence i suspect it might be a mix effect of some kind.

Can you help with this?
If so, is there a way to illustrate the product's impact on the total average?

I hope you can help.



br, Alex