restrictive covenants the terms of the 2017 credit facility and certain of our senior unsecured notes include certain restrictions and covenants which may limit , among other things , our ability to pay dividends , make certain types of investments , incur additional indebtedness , incur liens and enter into negative pledge agreements and dispose of assets , and which require compliance with financial ratios relating to the maximum ratio of total indebtedness to total asset value , a minimum ratio of ebitda to fixed charges , a maximum ratio of secured indebtedness to total asset value and a maximum ratio of unsecured indebtedness to unencumbered asset value . the dividend restriction referred to above provides that , we will not during any time when a default is continuing , make distributions with respect to common stock or other equity interests , except to enable the company to continue to qualify as a reit for federal income tax purposes . as of december a031 , 2017 and 2016 , we were in compliance with all such covenants . junior subordinated deferrable interest debentures in june a02005 , the company and the operating partnership issued $ 100.0 a0million in unsecured trust preferred securities through a newly formed trust , sl a0green capital trust i , or the trust , which is a wholly-owned subsidiary of the operating partnership . the securities mature in 2035 and bear interest at a floating rate of 125 a0basis points over the three-month libor . interest payments may be deferred for a period of up to eight consecutive quarters if the operating partnership exercises its right to defer such payments . the trust preferred securities are redeemable at the option of the operating partnership , in whole or in part , with no prepayment premium . we do not consolidate the trust even though it is a variable interest entity as we are not the primary beneficiary . because the trust is not consolidated , we have recorded the debt on our consolidated balance sheets and the related payments are classified as interest expense . interest rate risk we are exposed to changes in interest rates primarily from our variable rate debt . our exposure to interest rate fluctuations are managed through either the use of interest rate derivative instru- ments and/or through our variable rate debt and preferred equity investments . a hypothetical 100 a0basis point increase in interest rates along the entire interest rate curve for a02017 would increase our consolidated annual interest cost , net of interest income from variable rate debt and preferred equity investments , by $ 2.7 a0mil- lion and would increase our share of joint venture annual interest cost by $ 17.2 a0million . at december a031 , 2017 , 61.5% ( 61.5 % ) of our $ 2.1 a0bil- lion debt and preferred equity portfolio is indexed to libor . we recognize most derivatives on the balance sheet at fair value . derivatives that are not hedges are adjusted to fair value through income . if a derivative is considered a hedge , depending on the nature of the hedge , changes in the fair value of the derivative will either be offset against the change in fair value of the hedged asset , liability , or firm commitment through earnings , or recog- nized in other comprehensive income until the hedged item is recognized in earnings . the ineffective portion of a derivative 2019s change in fair value is immediately recognized in a0earnings . our long-term debt of $ 4.3 a0billion bears interest at fixed rates , and therefore the fair value of these instruments is affected by changes in the market interest rates . our variable rate debt and variable rate joint venture debt as of december a031 , 2017 bore interest based on a spread of libor plus 100 a0basis points to libor plus 415 a0basis points . contractual obligations the combined aggregate principal maturities of mortgages and other loans payable , the 2017 credit facility , senior unsecured notes ( net of discount ) , trust preferred securities , our share of joint venture debt , including as-of-right extension options and put options , estimated interest expense , and our obligations under our capital lease and ground leases , as of december a031 , 2017 are as follows ( in a0thousands ) : .

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Row 1: , 2018, 2019, 2020, 2021, 2022, thereafter, total
Row 2: property mortgages and other loans, $ 153593, $ 42289, $ 703018, $ 11656, $ 208003, $ 1656623, $ 2775182
Row 3: mra facilities, 90809, 2014, 2014, 2014, 2014, 2014, 90809
Row 4: revolving credit facility, 2014, 2014, 2014, 2014, 2014, 40000, 40000
Row 5: unsecured term loans, 2014, 2014, 2014, 2014, 2014, 1500000, 1500000
Row 6: senior unsecured notes, 250000, 2014, 250000, 2014, 800000, 100000, 1400000
Row 7: trust preferred securities, 2014, 2014, 2014, 2014, 2014, 100000, 100000
Row 8: capital lease, 2387, 2411, 2620, 2794, 2794, 819894, 832900
Row 9: ground leases, 31049, 31066, 31436, 31628, 29472, 703254, 857905
Row 10: estimated interest expense, 226815, 218019, 184376, 163648, 155398, 281694, 1229950
Row 11: joint venture debt, 200250, 717682, 473809, 449740, 223330, 2119481, 4184292
Row 12: total, $ 954903, $ 1011467, $ 1645259, $ 659466, $ 1418997, $ 7320946, $ 13011038
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Question: what was the 2019 rate of decrease in estimated interest expense payments?
Program: subtract(226815, 218019), divide(#0, 226815)
Answer: 0.03878