I'm a little late to the conversation, but I helped a client with this same issue recently. The inventory sales analysis report only shows sales of INVENTORY items. So as you mentioned any miscellaneous charges, or AR sales will not appear. Also, you need to make sure the product lines for all items post sales to the revenue account. As others have mentioned, anything that hits the revenue account(s) that is not from SO will be missing on the inventory sales analysis. Once I made all of the adjustments, I came to within a few dollars. There is a number for ""inventory sales that did not hit the revenue account"", and ""revenue account postings that did not come from a sale of inventory"".