credit facility , which was amended in 2013 and 2012 . in march 2014 , the company 2019s credit facility was further amended to extend the maturity date to march 2019 . the amount of the aggregate commitment is $ 3.990 billion ( the 201c2014 credit facility 201d ) . the 2014 credit facility permits the company to request up to an additional $ 1.0 billion of borrowing capacity , subject to lender credit approval , increasing the overall size of the 2014 credit facility to an aggregate principal amount not to exceed $ 4.990 billion . interest on borrowings outstanding accrues at a rate based on the applicable london interbank offered rate plus a spread . the 2014 credit facility requires the company not to exceed a maximum leverage ratio ( ratio of net debt to earnings before interest , taxes , depreciation and amortization , where net debt equals total debt less unrestricted cash ) of 3 to 1 , which was satisfied with a ratio of less than 1 to 1 at december 31 , 2014 . the 2014 credit facility provides back-up liquidity , funds ongoing working capital for general corporate purposes and funds various investment opportunities . at december 31 , 2014 , the company had no amount outstanding under the 2014 credit facility . commercial paper program . on october 14 , 2009 , blackrock established a commercial paper program ( the 201ccp program 201d ) under which the company could issue unsecured commercial paper notes ( the 201ccp notes 201d ) on a private placement basis up to a maximum aggregate amount outstanding at any time of $ 3.0 billion . blackrock increased the maximum aggregate amount that could be borrowed under the cp program to $ 3.5 billion in 2011 and to $ 3.785 billion in 2012 . in april 2013 , blackrock increased the maximum aggregate amount for which the company could issue unsecured cp notes on a private-placement basis up to a maximum aggregate amount outstanding at any time of $ 3.990 billion . the cp program is currently supported by the 2014 credit facility . at december 31 , 2014 , blackrock had no cp notes outstanding . long-term borrowings the carrying value and fair value of long-term borrowings estimated using market prices at december 31 , 2014 included the following : ( in millions ) maturity amount unamortized discount carrying value fair value .
what portion of total long-term borrowings is due in the next 36 months?
long-term borrowings at december 31 , 2013 had a carrying value of $ 4.939 billion and a fair value of $ 5.284 billion determined using market prices at the end of december 2013 . 2024 notes . in march 2014 , the company issued $ 1.0 billion in aggregate principal amount of 3.50% ( 3.50 % ) senior unsecured and unsubordinated notes maturing on march 18 , 2024 ( the 201c2024 notes 201d ) . the net proceeds of the 2024 notes were used to refinance certain indebtedness which matured in the fourth quarter of 2014 . interest is payable semi-annually in arrears on march 18 and september 18 of each year , or approximately $ 35 million per year . the 2024 notes may be redeemed prior to maturity at any time in whole or in part at the option of the company at a 201cmake-whole 201d redemption price . the 2024 notes were issued at a discount of $ 3 million that is being amortized over the term of the notes . the company incurred approximately $ 6 million of debt issuance costs , which are being amortized over the term of the 2024 notes . at december 31 , 2014 , $ 6 million of unamortized debt issuance costs was included in other assets on the consolidated statement of financial condition . 2015 and 2022 notes . in may 2012 , the company issued $ 1.5 billion in aggregate principal amount of unsecured unsubordinated obligations . these notes were issued as two separate series of senior debt securities , including $ 750 million of 1.375% ( 1.375 % ) notes maturing in june 2015 ( the 201c2015 notes 201d ) and $ 750 million of 3.375% ( 3.375 % ) notes maturing in june 2022 ( the 201c2022 notes 201d ) . net proceeds were used to fund the repurchase of blackrock 2019s common stock and series b preferred from barclays and affiliates and for general corporate purposes . interest on the 2015 notes and the 2022 notes of approximately $ 10 million and $ 25 million per year , respectively , is payable semi-annually on june 1 and december 1 of each year , which commenced december 1 , 2012 . the 2015 notes and 2022 notes may be redeemed prior to maturity at any time in whole or in part at the option of the company at a 201cmake-whole 201d redemption price . the 201cmake-whole 201d redemption price represents a price , subject to the specific terms of the 2015 and 2022 notes and related indenture , that is the greater of ( a ) par value and ( b ) the present value of future payments that will not be paid because of an early redemption , which is discounted at a fixed spread over a comparable treasury security . the 2015 notes and 2022 notes were issued at a discount of $ 5 million that is being amortized over the term of the notes . the company incurred approximately $ 7 million of debt issuance costs , which are being amortized over the respective terms of the 2015 notes and 2022 notes . at december 31 , 2014 , $ 4 million of unamortized debt issuance costs was included in other assets on the consolidated statement of financial condition . 2021 notes . in may 2011 , the company issued $ 1.5 billion in aggregate principal amount of unsecured unsubordinated obligations . these notes were issued as two separate series of senior debt securities , including $ 750 million of 4.25% ( 4.25 % ) notes maturing in may 2021 and $ 750 million of floating rate notes ( 201c2013 floating rate notes 201d ) , which were repaid in may 2013 at maturity . net proceeds of this offering were used to fund the repurchase of blackrock 2019s series b preferred from affiliates of merrill lynch & co. , inc . ( 201cmerrill lynch 201d ) . interest .