Abstract: A point-of-sale interface receives point-of-sale quantities for a number of individual items, as well as point-of-sale quantity for a miscellaneous group item that includes undifferentiated sales of one or more of the individual items. An item indexer calculates an item index for at least one individual item, the item index comprising a fraction of the miscellaneous group item sales attributable to the individual item. A sales disambiguator then computes a revised point-of-sale quantity for the at least one individual item using the item index and the point-of-sale quantities for the miscellaneous group item and the at least one individual item.