f0b7 positive train control 2013 in response to a legislative mandate to implement ptc by the end of 2015 , we expect to spend approximately $ 335 million during 2012 on developing and deploying ptc .we currently estimate that ptc in accordance with implementing rules issued by the federal rail administration ( fra ) will cost us approximately $ 2 billion by the end of 2015 .this includes costs for installing the new system along our tracks , upgrading locomotives to work with the new system , and adding digital data communication equipment so all the parts of the system can communicate with each other .during 2012 , we plan to continue testing the technology to evaluate its effectiveness .f0b7 financial expectations 2013 we are cautious about the economic environment but anticipate slow but steady volume growth that will exceed 2011 levels .coupled with price , on-going network improvements and operational productivity initiatives , we expect earnings that exceed 2011 earnings .results of operations operating revenues millions 2011 2010 2009 % (  % ) change 2011 v 2010 % (  % ) change 2010 v 2009 .
[['millions', '2011', '2010', '2009', '% (  % ) change 2011 v 2010', '% (  % ) change 2010 v 2009'], ['freight revenues', '$ 18508', '$ 16069', '$ 13373', '15% ( 15 % )', '20% ( 20 % )'], ['other revenues', '1049', '896', '770', '17', '16'], ['total', '$ 19557', '$ 16965', '$ 14143', '15% ( 15 % )', '20% ( 20 % )']]
we generate freight revenues by transporting freight or other materials from our six commodity groups .freight revenues vary with volume ( carloads ) and average revenue per car ( arc ) .changes in price , traffic mix and fuel surcharges drive arc .we provide some of our customers with contractual incentives for meeting or exceeding specified cumulative volumes or shipping to and from specific locations , which we record as reductions to freight revenues based on the actual or projected future shipments .we recognize freight revenues as shipments move from origin to destination .we allocate freight revenues between reporting periods based on the relative transit time in each reporting period and recognize expenses as we incur them .other revenues include revenues earned by our subsidiaries , revenues from our commuter rail operations , and accessorial revenues , which we earn when customers retain equipment owned or controlled by us or when we perform additional services such as switching or storage .we recognize other revenues as we perform services or meet contractual obligations .freight revenues for all six commodity groups increased during 2011 compared to 2010 , while volume increased in all except intermodal .increased demand in many market sectors , with particularly strong growth in chemical , industrial products , and automotive shipments for the year , generated the increases .arc increased 12% ( 12 % ) , driven by higher fuel cost recoveries and core pricing gains .fuel cost recoveries include fuel surcharge revenue and the impact of resetting the base fuel price for certain traffic , which is described below in more detail .higher fuel prices , volume growth , and new fuel surcharge provisions in renegotiated contracts all combined to increase revenues from fuel surcharges .freight revenues and volume levels for all six commodity groups increased during 2010 as a result of economic improvement in many market sectors .we experienced particularly strong volume growth in automotive , intermodal , and industrial products shipments .core pricing gains and higher fuel surcharges also increased freight revenues and drove a 6% ( 6 % ) improvement in arc .our fuel surcharge programs ( excluding index-based contract escalators that contain some provision for fuel ) generated freight revenues of $ 2.2 billion , $ 1.2 billion , and $ 605 million in 2011 , 2010 , and 2009 , respectively .higher fuel prices , volume growth , and new fuel surcharge provisions in contracts renegotiated during the year increased fuel surcharge amounts in 2011 and 2010 .furthermore , for certain periods during 2009 , fuel prices dropped below the base at which our mileage-based fuel surcharge begins , which resulted in no fuel surcharge recovery for associated shipments during those periods .additionally , fuel surcharge revenue is not entirely comparable to prior periods as we continue to convert portions of our non-regulated traffic to mileage-based fuel surcharge programs .in 2011 , other revenues increased from 2010 due primarily to higher revenues at our subsidiaries that broker intermodal and automotive services. .

Question: fuel surcharge programs represented what share of revenue in 2010?
Answer: 7.1%