is expected to begin by late-2018 , after the necessary information technology infrastructure is in place . entergy louisiana proposed to recover the cost of ami through the implementation of a customer charge , net of certain benefits , phased in over the period 2019 through 2022 . the parties reached an uncontested stipulation permitting implementation of entergy louisiana 2019s proposed ami system , with modifications to the proposed customer charge . in july 2017 the lpsc approved the stipulation . entergy louisiana expects to recover the undepreciated balance of its existing meters through a regulatory asset at current depreciation rates . sources of capital entergy louisiana 2019s sources to meet its capital requirements include : 2022 internally generated funds ; 2022 cash on hand ; 2022 debt or preferred membership interest issuances ; and 2022 bank financing under new or existing facilities . entergy louisiana may refinance , redeem , or otherwise retire debt prior to maturity , to the extent market conditions and interest rates are favorable . all debt and common and preferred membership interest issuances by entergy louisiana require prior regulatory approval . preferred membership interest and debt issuances are also subject to issuance tests set forth in its bond indentures and other agreements . entergy louisiana has sufficient capacity under these tests to meet its foreseeable capital needs . entergy louisiana 2019s receivables from the money pool were as follows as of december 31 for each of the following years. .
what percent higher yields from the money pool in the years 2016 and 2017 , than the years 2014 and 2015?
see note 4 to the financial statements for a description of the money pool . entergy louisiana has a credit facility in the amount of $ 350 million scheduled to expire in august 2022 . the credit facility allows entergy louisiana to issue letters of credit against $ 15 million of the borrowing capacity of the facility . as of december 31 , 2017 , there were no cash borrowings and a $ 9.1 million letter of credit outstanding under the credit facility . in addition , entergy louisiana is a party to an uncommitted letter of credit facility as a means to post collateral to support its obligations to miso . a0 as of december 31 , 2017 , a $ 29.7 million letter of credit was outstanding under entergy louisiana 2019s uncommitted letter of credit a0facility . see note 4 to the financial statements for additional discussion of the credit facilities . the entergy louisiana nuclear fuel company variable interest entities have two separate credit facilities , one in the amount of $ 105 million and one in the amount of $ 85 million , both scheduled to expire in may 2019 . as of december 31 , 2017 , $ 65.7 million of loans were outstanding under the credit facility for the entergy louisiana river bend nuclear fuel company variable interest entity . as of december 31 , 2017 , $ 43.5 million in letters of credit to support a like amount of commercial paper issued and $ 36.4 million in loans were outstanding under the entergy louisiana waterford nuclear fuel company variable interest entity credit facility . see note 4 to the financial statements for additional discussion of the nuclear fuel company variable interest entity credit facilities . entergy louisiana , llc and subsidiaries management 2019s financial discussion and analysis .