Current inventory by Item by Store

Hi,
I am very new to JET reports and I am trying to get my current stock on hand by store by item. The only way I have figured out how to do it is to use the Value Entry table and sum up invoiced Quantity. Although this works the file size is huge and will only get larger. Is there any table that has already calculated what current inventory is by Store/Item? I know that the Item table has current inventory at the Item level, but I need it by store/Item.

Thanks for any help!