definiens: — shall mean, on a Pr oduct - by - Product basis, an amount equal to the product obtained by multiplying ( a ) a fraction, the numerator of which is the subject Product sales in the subject c ountry in the Territory by [COMPANY] and its Affiliates, based upon the IMS Data for the thr ee ( 3 ) month period immediately preceding the Transaction Event, and the denominato r of which is the sum of the numerator plus the applicable Competing Product sal es in the subject country in the Territory based upon the IMS Data for the three ( 3 ) month period immediately preceding the Transaction Event, by ( b ) the [COMPANY] M argin ; provided, however, that if such three ( 3 ) month sales data is not available fo r either the Product or the Competing Product, then the Revised [COMPANY] Margin shall be dee med to be XXXXX percent ( XXXXX% ) of the Profit unless and until the Parties otherwise agree in good faith, taking into account the principles underlying the a bove formula and the relative commercial potential of each such Product and Compe ting Product . For the purposes of calculating the Revised [COMPANY] Margin, Net Sales, Manufacturing Costs, and Profit for a Competing Product, shall be calculated in the same manner as Net Sales, Manufacturing Costs, and Profit are calculated for a Product hereunder