{"pre_text": ["in connection with our assessment of impairment we recorded gross other-than-temporary impairment of $ 1.15 billion for 2009 , compared to $ 122 million for 2008 .", "of the total recorded , $ 227 million related to credit and was recognized in our consolidated statement of income .", "the remaining $ 928 million related to factors other than credit , more fully discussed below , and was recognized , net of related taxes , in oci in our consolidated statement of condition .", "the $ 227 million was composed of $ 151 million associated with expected credit losses , $ 54 million related to management 2019s decision to sell the impaired securities prior to their recovery in value , and $ 22 million related to adverse changes in the timing of expected future cash flows from the securities .", "the majority of the impairment losses related to non-agency securities collateralized by mortgages , for which management concluded had experienced credit losses based on the present value of the securities 2019 expected future cash flows .", "these securities are classified as asset-backed securities in the foregoing investment securities tables .", "as described in note 1 , management periodically reviews the fair values of investment securities to determine if other-than-temporary impairment has occurred .", "this review encompasses all investment securities and includes such quantitative factors as current and expected future interest rates and the length of time that a security 2019s cost basis has exceeded its fair value , and includes investment securities for which we have issuer- specific concerns regardless of quantitative factors .", "gains and losses related to investment securities were as follows for the years ended december 31: ."], "post_text": ["( 1 ) these losses were recognized as a component of oci ; see note 12 .", "we conduct periodic reviews to evaluate each security that is impaired .", "impairment exists when the current fair value of an individual security is below its amortized cost basis .", "for debt securities available for sale and held to maturity , other-than-temporary impairment is recorded in our consolidated statement of income when management intends to sell ( or may be required to sell ) securities before they recover in value , or when management expects the present value of cash flows expected to be collected to be less than the amortized cost of the impaired security ( a credit loss ) .", "our review of impaired securities generally includes : 2022 the identification and evaluation of securities that have indications of possible other-than-temporary impairment , such as issuer-specific concerns including deteriorating financial condition or bankruptcy ; 2022 the analysis of expected future cash flows of securities , based on quantitative and qualitative factors ; 2022 the analysis of the collectability of those future cash flows , including information about past events , current conditions and reasonable and supportable forecasts ; 2022 the analysis of individual impaired securities , including consideration of the length of time the security has been in an unrealized loss position and the anticipated recovery period ; 2022 the discussion of evidential matter , including an evaluation of factors or triggers that could cause individual securities to be deemed other-than-temporarily impaired and those that would not support other-than-temporary impairment ; and 2022 documentation of the results of these analyses .", "factors considered in determining whether impairment is other than temporary include : 2022 the length of time the security has been impaired; ."], "table": [["( in millions )", "2009", "2008", "2007"], ["gross gains from sales of available-for-sale securities", "$ 418", "$ 100", "$ 24"], ["gross losses from sales of available-for-sale securities", "-50 ( 50 )", "-32 ( 32 )", "-17 ( 17 )"], ["gross losses from other-than-temporary impairment", "-1155 ( 1155 )", "-122 ( 122 )", "-34 ( 34 )"], ["losses not related to credit ( 1 )", "928", "2014", "2014"], ["net impairment losses", "-227 ( 227 )", "-122 ( 122 )", "-34 ( 34 )"], ["gains ( losses ) related to investment securities net", "$ 141", "$ -54 ( 54 )", "$ -27 ( 27 )"]], "table_ori": [["(In millions)", "2009", "2008", "2007"], ["Gross gains from sales of available-for-sale securities", "$418", "$100", "$24"], ["Gross losses from sales of available-for-sale securities", "(50)", "(32)", "(17)"], ["Gross losses from other-than-temporary impairment", "(1,155)", "(122)", "(34)"], ["Losses not related to credit<sup>(1)</sup>", "928", "—", "—"], ["Net impairment losses", "(227)", "(122)", "(34)"], ["Gains (Losses) related to investment securities, net", "$141", "$(54)", "$(27)"]]}

Question: what was the average gross gains from sales of available-for-sale securities from 2007 to 2009
Evidence:
table_1: ( in millions ) the gross gains from sales of available-for-sale securities of 2009 is $ 418 ; the gross gains from sales of available-for-sale securities of 2008 is $ 100 ; the gross gains from sales of available-for-sale securities of 2007 is $ 24 ;
Program: add(418, 100), add(#0, 24), add(#1, const_3), divide(#2, const_2)
Answer:
str_answer: 180.7
exe_answer: 272.5