definiens: means the proportion of total sales of [COMPANY] and i ts Affiliates represented by sales of the Product that are used t o calculate the HCR Fees associated with the Produc t, only if such proportion is expressly reported by th e United States Department of Treasury when it invoices the HCR Fees to [COMPANY] and its Affiliates ; p rovided, however, that if the United States Department of Treasury does not report such proport ion as provided in the foregoing, then means the total dollar value of sales of the Prod uct under the [COMPANY] NDC in the relevant calendar year to government purchasers inc luded in the calculation of the HCR Fees divided by the total dollar value of sales of all products of [COMPANY] and its Affiliates in the relevant calendar ye ar to government purchasers included in the calculation o f the HCR Fees, based on data in [COMPANY] 's accounting system for such sales