Why is my average gross sales unit price lower than my menu price?

[ycsf]

When I export an item sales summary report and apply a formula to see what the average unit gross sales price was, it never matches the menu price. The formula is simply GROSS ITEM SALES / ITEMS SOLD. I'm trying to figure out why this would be. Keep in mind these are gross sales, so the answer is not refunds or comps/discounts.

[RHatch]

How are you compairing it to your menu price?  I understand how you are getting the the average from your sales.  But are you conpairing that to the Average Menu price?