for marketing . there are several methods that can be used to determine the estimated fair value of the ipr&d acquired in a business combination . we utilized the 201cincome method , 201d which applies a probability weighting to the estimated future net cash fl ows that are derived from projected sales revenues and estimated costs . these projec- tions are based on factors such as relevant market size , patent protection , historical pricing of similar products , and expected industry trends . the estimated future net cash fl ows are then discounted to the present value using an appropriate discount rate . this analysis is performed for each project independently . in accordance with fin 4 , applicability of fasb statement no . 2 to business combinations accounted for by the purchase method , these acquired ipr&d intangible assets totaling $ 4.71 billion and $ 340.5 million in 2008 and 2007 , respectively , were expensed immediately subsequent to the acquisition because the products had no alternative future use . the ongoing activities with respect to each of these products in development are not material to our research and development expenses . in addition to the acquisitions of businesses , we also acquired several products in development . the acquired ipr&d related to these products of $ 122.0 million and $ 405.1 million in 2008 and 2007 , respectively , was also writ- ten off by a charge to income immediately upon acquisition because the products had no alternative future use . imclone acquisition on november 24 , 2008 , we acquired all of the outstanding shares of imclone systems inc . ( imclone ) , a biopharma- ceutical company focused on advancing oncology care , for a total purchase price of approximately $ 6.5 billion , which was fi nanced through borrowings . this strategic combination will offer both targeted therapies and oncolytic agents along with a pipeline spanning all phases of clinical development . the combination also expands our bio- technology capabilities . the acquisition has been accounted for as a business combination under the purchase method of accounting , resulting in goodwill of $ 419.5 million . no portion of this goodwill is expected to be deductible for tax purposes . allocation of purchase price we are currently determining the fair values of a signifi cant portion of these net assets . the purchase price has been preliminarily allocated based on an estimate of the fair value of assets acquired and liabilities assumed as of the date of acquisition . the fi nal determination of these fair values will be completed as soon as possible but no later than one year from the acquisition date . although the fi nal determination may result in asset and liability fair values that are different than the preliminary estimates of these amounts included herein , it is not expected that those differences will be material to our fi nancial results . estimated fair value at november 24 , 2008 .

$ 982.9: inventories: 136.2
developed product technology ( erbitux ) 1: 1057.9
goodwill: 419.5
property and equipment: 339.8
debt assumed: -600
deferred taxes: -315
deferred income: -127.7
other assets and liabilities 2014 net: -72.1
acquired in-process research and development: 4685.4
total purchase price: 6506.9

1this intangible asset will be amortized on a straight-line basis through 2023 in the u.s . and 2018 in the rest of the world . all of the estimated fair value of the acquired ipr&d is attributable to oncology-related products in develop- ment , including $ 1.33 billion to line extensions for erbitux . a signifi cant portion ( 81 percent ) of the remaining value of acquired ipr&d is attributable to two compounds in phase iii clinical testing and one compound in phase ii clini- cal testing , all targeted to treat various forms of cancers . the discount rate we used in valuing the acquired ipr&d projects was 13.5 percent , and the charge for acquired ipr&d of $ 4.69 billion recorded in the fourth quarter of 2008 , was not deductible for tax purposes . pro forma financial information the following unaudited pro forma fi nancial information presents the combined results of our operations with .

Questions:
how many years are between 2023 and 2008?
what is the value of developed product technology?
what is that value divided by the number of years?

Answers:
15
1057.9
70.53