I need to change the way the "GAP" gets calculated within the attached Straight Table. The different parts to the formula are...
Average Sales = Total Sales / # Stores with Sales
If the Sales value (by Barcode/Store) is less than the Average, then the GAP = Average Sales - Sales (by Barcode / Store)
The easy part is to add the Average Sales column, but how would I test the Sales value (by Barcode/Store) against the Average Sales value without the Store being included withing this table?