2009 levels , we returned a portion of these assets to active service . at the end of 2010 , we continued to maintain in storage approximately 17% ( 17 % ) of our multiple purpose locomotives and 14% ( 14 % ) of our freight car inventory , reflecting our ability to effectively leverage our assets as volumes return to our network . 2022 fuel prices 2013 fuel prices generally increased throughout 2010 as the economy improved . our average diesel fuel price per gallon increased nearly 20% ( 20 % ) from january to december of 2010 , driven by higher crude oil barrel prices and conversion spreads . compared to 2009 , our diesel fuel price per gallon consumed increased 31% ( 31 % ) , driving operating expenses up by $ 566 million ( excluding any impact from year-over-year volume increases ) . to partially offset the effect of higher fuel prices , we reduced our consumption rate by 3% ( 3 % ) during the year , saving approximately 27 million gallons of fuel . the use of newer , more fuel efficient locomotives ; increased use of distributed locomotive power ( the practice of distributing locomotives throughout a train rather than positioning them all in the lead resulting in safer and more efficient train operations ) ; fuel conservation programs ; and efficient network operations and asset utilization all contributed to this improvement . 2022 free cash flow 2013 cash generated by operating activities ( adjusted for the reclassification of our receivables securitization facility ) totaled $ 4.5 billion , yielding record free cash flow of $ 1.4 billion in 2010 . free cash flow is defined as cash provided by operating activities ( adjusted for the reclassification of our receivables securitization facility ) , less cash used in investing activities and dividends paid . free cash flow is not considered a financial measure under accounting principles generally accepted in the u.s . ( gaap ) by sec regulation g and item 10 of sec regulation s-k . we believe free cash flow is important in evaluating our financial performance and measures our ability to generate cash without additional external financings . free cash flow should be considered in addition to , rather than as a substitute for , cash provided by operating activities . the following table reconciles cash provided by operating activities ( gaap measure ) to free cash flow ( non-gaap measure ) : millions 2010 2009 2008 .
what is the mathematical range , in millions , for total free cash flow from 2008-2010?
[a] effective january 1 , 2010 , a new accounting standard required us to account for receivables transferred under our receivables securitization facility as secured borrowings in our consolidated statements of financial position and as financing activities in our consolidated statements of cash flows . the receivables securitization facility is included in our free cash flow calculation to adjust cash provided by operating activities as though our receivables securitization facility had been accounted for under the new accounting standard for all periods presented . 2011 outlook 2022 safety 2013 operating a safe railroad benefits our employees , our customers , our shareholders , and the public . we will continue using a multi-faceted approach to safety , utilizing technology , risk assessment , quality control , and training , and engaging our employees . we will continue implementing total safety culture ( tsc ) throughout our operations . tsc is designed to establish , maintain , reinforce , and promote safe practices among co-workers . this process allows us to identify and implement best practices for employee and operational safety . reducing grade crossing incidents is a critical aspect of our safety programs , and we will continue our efforts to maintain and close crossings ; install video cameras on locomotives ; and educate the public and law enforcement agencies about crossing safety through a combination of our own programs ( including risk assessment strategies ) , various industry programs , and engaging local communities . 2022 transportation plan 2013 to build upon our success in recent years , we will continue evaluating traffic flows and network logistic patterns , which can be quite dynamic , to identify additional opportunities to simplify operations , remove network variability , and improve network efficiency and asset utilization . we plan to adjust manpower and our locomotive and rail car fleets to meet customer needs and put .