other operating/performance and financial statistics we report key railroad performance measures weekly to the association of american railroads ( aar ) , including carloads , average daily inventory of rail cars on our system , average train speed , and average terminal dwell time . we provide this data on our website at www.up.com/investors/reports/index.shtml . operating/performance statistics included in the table below are railroad performance measures reported to the aar : 2008 2007 2006 % (  % ) change 2008 v 2007 % (  % ) change 2007 v 2006 .

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Row 1: , 2008, 2007, 2006, % (  % ) change 2008 v 2007, % (  % ) change 2007 v 2006
Row 2: average train speed ( miles per hour ), 23.5, 21.8, 21.4, 8 % (  % ), 2 % (  % )
Row 3: average terminal dwell time ( hours ), 24.9, 25.1, 27.2, ( 1 ) % (  % ), ( 8 ) % (  % )
Row 4: average rail car inventory ( thousands ), 300.7, 309.9, 321.6, ( 3 ) % (  % ), ( 4 ) % (  % )
Row 5: gross ton-miles ( billions ), 1020.4, 1052.3, 1072.5, ( 3 ) % (  % ), ( 2 ) % (  % )
Row 6: revenue ton-miles ( billions ), 562.6, 561.8, 565.2, -, ( 1 ) % (  % )
Row 7: operating ratio, 77.3, 79.3, 81.5, 2.0 pt, 2.2 pt
Row 8: employees ( average ), 48242, 50089, 50739, ( 4 ) % (  % ), ( 1 ) % (  % )
Row 9: customer satisfaction index, 83, 79, 72, 4 pt, 7 pt
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average train speed 2013 average train speed is calculated by dividing train miles by hours operated on our main lines between terminals . ongoing network management initiatives , productivity improvements , and lower volume levels contributed to 8% ( 8 % ) and 2% ( 2 % ) improvements in average train speed in 2008 and 2007 , respectively . average terminal dwell time 2013 average terminal dwell time is the average time that a rail car spends at our terminals . lower average terminal dwell time improves asset utilization and service . average terminal dwell time improved 1% ( 1 % ) and 8% ( 8 % ) in 2008 and 2007 , respectively . lower volumes combined with initiatives to more timely deliver rail cars to our interchange partners and customers improved dwell time in both periods . gross and revenue ton-miles 2013 gross ton-miles are calculated by multiplying the weight of loaded and empty freight cars by the number of miles hauled . revenue ton-miles are calculated by multiplying the weight of freight by the number of tariff miles . gross ton-miles decreased 3% ( 3 % ) , while revenue ton-miles were flat in 2008 compared to 2007 with commodity mix changes ( notably autos and coal ) explaining the variance in year over year growth between the two metrics . in 2007 , revenue ton-miles declined 1% ( 1 % ) in relation to the 1% ( 1 % ) reduction in carloadings compared to 2006 . gross ton-miles decreased 2% ( 2 % ) in 2007 driven by a mix shift in freight shipments . operating ratio 2013 operating ratio is defined as our operating expenses as a percentage of operating revenue . our operating ratios improved 2.0 points to 77.3% ( 77.3 % ) in 2008 and 2.2 points to 79.3% ( 79.3 % ) in 2007 . price increases , fuel cost recoveries , network management initiatives , and improved productivity more than offset the impact of higher fuel prices . employees 2013 productivity initiatives and lower volumes reduced employee levels throughout the company in 2008 versus 2007 . fewer train and engine personnel due to improved network productivity and 5% ( 5 % ) lower volume drove the change while productivity initiatives within the support organizations also contributed to a lower full-time equivalent force level . lower employee levels in 2007 versus 2006 .

Question: based on the operating/performance statistics what was the average operating ratio from 2006 to 2008
Program: add(77.3, 79.3), add(#0, 81.5)
Answer: 238.1