Pivot Table

[ggerotto]

I created a Pivot Table in order to group some of my elements. What do I have to do to get the sum of every element of the group?  The formula I use is the following: 

Final = (SUM((price - [cost])/price)*(SUM(count * price))/SUM(total count*price))

I don't know what this number means, but it's most certainly not the sum