Read the following texts and table with financial data from an S&P 500 earnings report carefully.Based on the question-answer history (if provided), answer the last question. The answer may require mathematical calculation based on the data provided.

Text: operating expenses millions 2012 2011 2010 % (  % ) change 2012 v 2011 % (  % ) change 2011 v 2010 . <table class='wikitable'><tr><td>1</td><td>millions</td><td>2012</td><td>2011</td><td>2010</td><td>% (  % ) change 2012 v 2011</td><td>% (  % ) change 2011 v 2010</td></tr><tr><td>2</td><td>compensation and benefits</td><td>$ 4685</td><td>$ 4681</td><td>$ 4314</td><td>-% ( - % )</td><td>9% ( 9 % )</td></tr><tr><td>3</td><td>fuel</td><td>3608</td><td>3581</td><td>2486</td><td>1</td><td>44</td></tr><tr><td>4</td><td>purchased services and materials</td><td>2143</td><td>2005</td><td>1836</td><td>7</td><td>9</td></tr><tr><td>5</td><td>depreciation</td><td>1760</td><td>1617</td><td>1487</td><td>9</td><td>9</td></tr><tr><td>6</td><td>equipment and other rents</td><td>1197</td><td>1167</td><td>1142</td><td>3</td><td>2</td></tr><tr><td>7</td><td>other</td><td>788</td><td>782</td><td>719</td><td>1</td><td>9</td></tr><tr><td>8</td><td>total</td><td>$ 14181</td><td>$ 13833</td><td>$ 11984</td><td>3% ( 3 % )</td><td>15% ( 15 % )</td></tr></table> operating expenses increased $ 348 million in 2012 versus 2011 . depreciation , wage and benefit inflation , higher fuel prices and volume- related trucking services purchased by our logistics subsidiaries , contributed to higher expenses during the year . efficiency gains , volume related fuel savings ( 2% ( 2 % ) fewer gallons of fuel consumed ) and $ 38 million of weather related expenses in 2011 , which favorably affects the comparison , partially offset the cost increase . operating expenses increased $ 1.8 billion in 2011 versus 2010 . our fuel price per gallon rose 36% ( 36 % ) during 2011 , accounting for $ 922 million of the increase . wage and benefit inflation , volume-related costs , depreciation , and property taxes also contributed to higher expenses . expenses increased $ 20 million for costs related to the flooding in the midwest and $ 18 million due to the impact of severe heat and drought in the south , primarily texas . cost savings from productivity improvements and better resource utilization partially offset these increases . a $ 45 million one-time payment relating to a transaction with csx intermodal , inc ( csxi ) increased operating expenses during the first quarter of 2010 , which favorably affects the comparison of operating expenses in 2011 to those in 2010 . compensation and benefits 2013 compensation and benefits include wages , payroll taxes , health and welfare costs , pension costs , other postretirement benefits , and incentive costs . expenses in 2012 were essentially flat versus 2011 as operational improvements and cost reductions offset general wage and benefit inflation and higher pension and other postretirement benefits . in addition , weather related costs increased these expenses in 2011 . a combination of general wage and benefit inflation , volume-related expenses , higher training costs associated with new hires , additional crew costs due to speed restrictions caused by the midwest flooding and heat and drought in the south , and higher pension expense drove the increase during 2011 compared to 2010 . fuel 2013 fuel includes locomotive fuel and gasoline for highway and non-highway vehicles and heavy equipment . higher locomotive diesel fuel prices , which averaged $ 3.22 per gallon ( including taxes and transportation costs ) in 2012 , compared to $ 3.12 in 2011 , increased expenses by $ 105 million . volume , as measured by gross ton-miles , decreased 2% ( 2 % ) in 2012 versus 2011 , driving expense down . the fuel consumption rate was flat year-over-year . higher locomotive diesel fuel prices , which averaged $ 3.12 ( including taxes and transportation costs ) in 2011 , compared to $ 2.29 per gallon in 2010 , increased expenses by $ 922 million . in addition , higher gasoline prices for highway and non-highway vehicles also increased year-over-year . volume , as measured by gross ton-miles , increased 5% ( 5 % ) in 2011 versus 2010 , driving expense up by $ 122 million . purchased services and materials 2013 expense for purchased services and materials includes the costs of services purchased from outside contractors and other service providers ( including equipment 2012 operating expenses .
Question: what was the per-gallon cost of locomotive diesel fuel prices in 2012?
Answer: 3.22
Question: and in 2011?
Answer: 3.12
Question: so what was the difference between these years?
Answer: 0.1
Question: using this value, what was the estimated fuel cost for 2012?
Answer: 1050.0
Question: and converted to the billions?

user
1050000000.0
assistant