Is it possible to make pivot table with "%difference to previous" Grand totals with arrows?

[szita2000]

Hi guys.

I am building a Pivot which will grow with data each day.
I sorted the refresh with VBA, and I did setup my value fields to show values as % Difference from previous day.

What I couldn't figure out, how to create a conditional formatting that will add those up/down triangles to my Grand totals (stock market style)
That is based on the previous day. So it is comparing to the previous day. - If it is up then green up arrow if it is down then red down arrow.

Would I simply write a conditional formatting formula that points to the left of the cell and evaluate that?
Also, I am aware on how to add the custom triangles in Custom formatting, and make the cell value red/green, but that would be based on if the cell value, if it is above zero or not.

Is there a way to modify the built in icon sets conditional formattings to do this?

Any idea of what I could try?

Thanks

Thomas