{"pre_text": ["meet customer needs and put us in a position to handle demand changes .", "we will also continue utilizing industrial engineering techniques to improve productivity .", "2022 fuel prices 2013 uncertainty about the economy makes fuel price projections difficult , and we could see volatile fuel prices during the year , as they are sensitive to global and u.s .", "domestic demand , refining capacity , geopolitical issues and events , weather conditions and other factors .", "to reduce the impact of fuel price on earnings , we will continue to seek recovery from our customers through our fuel surcharge programs and to expand our fuel conservation efforts .", "2022 capital plan 2013 in 2010 , we plan to make total capital investments of approximately $ 2.5 billion , including expenditures for ptc , which may be revised if business conditions or new laws or regulations affect our ability to generate sufficient returns on these investments .", "see further discussion in this item 7 under liquidity and capital resources 2013 capital plan .", "2022 positive train control ( ptc ) 2013 in response to a legislative mandate to implement ptc by the end of 2015 , we expect to spend approximately $ 200 million during 2010 on the development of ptc .", "we currently estimate that ptc will cost us approximately $ 1.4 billion to implement by the end of 2015 , in accordance with rules issued by the fra .", "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 .", "2022 financial expectations 2013 we remain cautious about economic conditions but expect volume to increase from 2009 levels .", "in addition , we anticipate continued pricing opportunities and further productivity improvements .", "results of operations operating revenues millions of dollars 2009 2008 2007 % (  % ) change 2009 v 2008 % (  % ) change 2008 v 2007 ."], "post_text": ["freight revenues are revenues generated 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 a reduction to freight revenues based on the actual or projected future shipments .", "we recognize freight revenues on a percentage-of-completion basis as freight moves 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 and volume levels for all six commodity groups decreased during 2009 , reflecting continued economic weakness .", "we experienced the largest volume declines in automotive and industrial ."], "table": [["millions of dollars", "2009", "2008", "2007", "% (  % ) change 2009 v 2008", "% (  % ) change 2008 v 2007"], ["freight revenues", "$ 13373", "$ 17118", "$ 15486", "( 22 ) % (  % )", "11% ( 11 % )"], ["other revenues", "770", "852", "797", "-10 ( 10 )", "7"], ["total", "$ 14143", "$ 17970", "$ 16283", "( 21 ) % (  % )", "10% ( 10 % )"]], "table_ori": [["<i>Millions of Dollars</i>", "<i>2009</i>", "<i>2008</i>", "<i>2007</i>", "<i>% Change 2009 v 2008</i>", "<i>% Change 2008 v 2007</i>"], ["Freight revenues", "$13,373", "$17,118", "$15,486", "(22)%", "11%"], ["Other revenues", "770", "852", "797", "(10)", "7"], ["Total", "$14,143", "$17,970", "$16,283", "(21)%", "10%"]]}

Question: what was the change in total revenue in millions from 2007 to 2008?
Evidence:
table_3: millions of dollars the total of 2009 is $ 14143 ; the total of 2008 is $ 17970 ; the total of 2007 is $ 16283 ; the total of % ( % ) change 2009 v 2008 is ( 21 ) % ( % ) ; the total of % ( % ) change 2008 v 2007 is 10% ( 10 % ) ;
Program: subtract(17970, 16283)
Answer:
str_answer: 1687
exe_answer: 1687