Read the following texts and table with financial data from an S&P 500 earnings report carefully.Based on the question-answer history (if provided), answer the last question. The answer may require mathematical calculation based on the data provided.


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 . <table class='wikitable'><tr><td>1</td><td>cash and short-term investments</td><td>$ 982.9</td></tr><tr><td>2</td><td>inventories</td><td>136.2</td></tr><tr><td>3</td><td>developed product technology ( erbitux ) 1</td><td>1057.9</td></tr><tr><td>4</td><td>goodwill</td><td>419.5</td></tr><tr><td>5</td><td>property and equipment</td><td>339.8</td></tr><tr><td>6</td><td>debt assumed</td><td>-600.0 ( 600.0 )</td></tr><tr><td>7</td><td>deferred taxes</td><td>-315.0 ( 315.0 )</td></tr><tr><td>8</td><td>deferred income</td><td>-127.7 ( 127.7 )</td></tr><tr><td>9</td><td>other assets and liabilities 2014 net</td><td>-72.1 ( 72.1 )</td></tr><tr><td>10</td><td>acquired in-process research and development</td><td>4685.4</td></tr><tr><td>11</td><td>total purchase price</td><td>$ 6506.9</td></tr></table> 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 .
Question: how many years are between 2023 and 2008?
Answer: 15.0
Question: what is the value of developed product technology?

1057.9