the goldman sachs group , inc . and subsidiaries notes to consolidated financial statements the table below presents a summary of level 3 financial assets. .
for level 3 financial assets in millions , for 2018 and 2017 , what was the largest balance of cash instruments?
level 3 financial assets as of december 2018 increased compared with december 2017 , primarily reflecting an increase in level 3 cash instruments . see notes 6 through 8 for further information about level 3 financial assets ( including information about unrealized gains and losses related to level 3 financial assets and financial liabilities , and transfers in and out of level 3 ) . note 6 . cash instruments cash instruments include u.s . government and agency obligations , non-u.s . government and agency obligations , mortgage-backed loans and securities , corporate debt instruments , equity securities , investments in funds at nav , and other non-derivative financial instruments owned and financial instruments sold , but not yet purchased . see below for the types of cash instruments included in each level of the fair value hierarchy and the valuation techniques and significant inputs used to determine their fair values . see note 5 for an overview of the firm 2019s fair value measurement policies . level 1 cash instruments level 1 cash instruments include certain money market instruments , u.s . government obligations , most non-u.s . government obligations , certain government agency obligations , certain corporate debt instruments and actively traded listed equities . these instruments are valued using quoted prices for identical unrestricted instruments in active markets . the firm defines active markets for equity instruments based on the average daily trading volume both in absolute terms and relative to the market capitalization for the instrument . the firm defines active markets for debt instruments based on both the average daily trading volume and the number of days with trading activity . level 2 cash instruments level 2 cash instruments include most money market instruments , most government agency obligations , certain non-u.s . government obligations , most mortgage-backed loans and securities , most corporate debt instruments , most state and municipal obligations , most other debt obligations , restricted or less liquid listed equities , commodities and certain lending commitments . valuations of level 2 cash instruments can be verified to quoted prices , recent trading activity for identical or similar instruments , broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency . consideration is given to the nature of the quotations ( e.g. , indicative or firm ) and the relationship of recent market activity to the prices provided from alternative pricing sources . valuation adjustments are typically made to level 2 cash instruments ( i ) if the cash instrument is subject to transfer restrictions and/or ( ii ) for other premiums and liquidity discounts that a market participant would require to arrive at fair value . valuation adjustments are generally based on market evidence . level 3 cash instruments level 3 cash instruments have one or more significant valuation inputs that are not observable . absent evidence to the contrary , level 3 cash instruments are initially valued at transaction price , which is considered to be the best initial estimate of fair value . subsequently , the firm uses other methodologies to determine fair value , which vary based on the type of instrument . valuation inputs and assumptions are changed when corroborated by substantive observable evidence , including values realized on sales . valuation techniques and significant inputs of level 3 cash instruments valuation techniques of level 3 cash instruments vary by instrument , but are generally based on discounted cash flow techniques . the valuation techniques and the nature of significant inputs used to determine the fair values of each type of level 3 cash instrument are described below : loans and securities backed by commercial real estate . loans and securities backed by commercial real estate are directly or indirectly collateralized by a single commercial real estate property or a portfolio of properties , and may include tranches of varying levels of subordination . significant inputs are generally determined based on relative value analyses and include : 2030 market yields implied by transactions of similar or related assets and/or current levels and changes in market indices such as the cmbx ( an index that tracks the performance of commercial mortgage bonds ) ; 118 goldman sachs 2018 form 10-k .