financial statement impact we believe that our accruals for sales returns , rebates , and discounts are reasonable and appropriate based on current facts and circumstances .
our global rebate and discount liabilities are included in sales rebates and discounts on our consolidated balance sheet .
our global sales return liability is included in other current liabilities and other noncurrent liabilities on our consolidated balance sheet .
as of december 31 , 2018 , a 5 percent change in our global sales return , rebate , and discount liability would have led to an approximate $ 275 million effect on our income before income taxes .
the portion of our global sales return , rebate , and discount liability resulting from sales of our products in the u.s .
was approximately 90 percent as of december 31 , 2018 and december 31 , 2017 .
the following represents a roll-forward of our most significant u.s .
pharmaceutical sales return , rebate , and discount liability balances , including managed care , medicare , and medicaid: .

(Dollars in millions)
2018
2017
Sales return, rebate, and discount liabilities, beginning of year
$4,172.0
$3,601.8
Reduction of net sales due to sales returns, discounts, and rebates<sup>(1)</sup>
12,529.6
10,603.4
Cash payments of discounts and rebates
(12,023.4)
(10,033.2)
Sales return, rebate, and discount liabilities, end of year
$4,678.2
$4,172.0

( 1 ) adjustments of the estimates for these returns , rebates , and discounts to actual results were approximately 1 percent of consolidated net sales for each of the years presented .
product litigation liabilities and other contingencies background and uncertainties product litigation liabilities and other contingencies are , by their nature , uncertain and based upon complex judgments and probabilities .
the factors we consider in developing our product litigation liability reserves and other contingent liability amounts include the merits and jurisdiction of the litigation , the nature and the number of other similar current and past matters , the nature of the product and the current assessment of the science subject to the litigation , and the likelihood of settlement and current state of settlement discussions , if any .
in addition , we accrue for certain product liability claims incurred , but not filed , to the extent we can formulate a reasonable estimate of their costs based primarily on historical claims experience and data regarding product usage .
we accrue legal defense costs expected to be incurred in connection with significant product liability contingencies when both probable and reasonably estimable .
we also consider the insurance coverage we have to diminish the exposure for periods covered by insurance .
in assessing our insurance coverage , we consider the policy coverage limits and exclusions , the potential for denial of coverage by the insurance company , the financial condition of the insurers , and the possibility of and length of time for collection .
due to a very restrictive market for product liability insurance , we are self-insured for product liability losses for all our currently marketed products .
in addition to insurance coverage , we also consider any third-party indemnification to which we are entitled or under which we are obligated .
with respect to our third-party indemnification rights , these considerations include the nature of the indemnification , the financial condition of the indemnifying party , and the possibility of and length of time for collection .
the litigation accruals and environmental liabilities and the related estimated insurance recoverables have been reflected on a gross basis as liabilities and assets , respectively , on our consolidated balance sheets .
impairment of indefinite-lived and long-lived assets background and uncertainties we review the carrying value of long-lived assets ( both intangible and tangible ) for potential impairment on a periodic basis and whenever events or changes in circumstances indicate the carrying value of an asset ( or asset group ) may not be recoverable .
we identify impairment by comparing the projected undiscounted cash flows to be generated by the asset ( or asset group ) to its carrying value .
if an impairment is identified , a loss is recorded equal to the excess of the asset 2019s net book value over its fair value , and the cost basis is adjusted .
goodwill and indefinite-lived intangible assets are reviewed for impairment at least annually and when certain impairment indicators are present .
when required , a comparison of fair value to the carrying amount of assets is performed to determine the amount of any impairment. .

Question: Analyse this data from a financial earnings document. what was the percentage change in reduction of net sales due to sales returns discounts and rebates between 2017 and 2018?
Choices:
0.00182
0
-0.18166
0.18166
12529.78166
Correct choice index: 3