approximately 710 asphalt-paving contractors , government entities ( states , counties , cities and townships ) and asphalt roofing shingle manufacturers . we also produce asphalt cements , polymerized asphalt , asphalt emulsions and industrial asphalts . retail marketing ssa , our wholly-owned subsidiary , sells gasoline and merchandise through owned and operated retail outlets primarily under the speedway ae and superamerica ae brands . diesel fuel is also sold at a number of these outlets . ssa retail outlets offer a wide variety of merchandise , such as prepared foods , beverages , and non-food items , as well as a significant number of proprietary items . as of december 31 , 2008 , ssa had 1617 retail outlets in nine states . sales of refined products through these retail outlets accounted for 15 percent of our refined product sales volumes in 2008 . revenues from sales of non-petroleum merchandise through these retail outlets totaled $ 2838 million in 2008 , $ 2796 million in 2007 and $ 2706 million in 2006 . the demand for gasoline is seasonal in a majority of ssa markets , usually with the highest demand during the summer driving season . profit levels from the sale of merchandise and services tend to be less volatile than profit levels from the retail sale of gasoline and diesel fuel . in october 2008 , we sold our interest in pilot travel centers llc ( 201cptc 201d ) , an operator of travel centers in the united states . pipeline transportation we own a system of pipelines through marathon pipe line llc ( 201cmpl 201d ) and ohio river pipe line llc ( 201corpl 201d ) , our wholly-owned subsidiaries . our pipeline systems transport crude oil and refined products primarily in the midwest and gulf coast regions to our refineries , our terminals and other pipeline systems . our mpl and orpl wholly-owned and undivided interest common carrier systems consist of 1815 miles of crude oil lines and 1826 miles of refined product lines comprising 34 systems located in 11 states . the mpl common carrier pipeline network is one of the largest petroleum pipeline systems in the united states , based on total barrels delivered . our common carrier pipeline systems are subject to state and federal energy regulatory commission regulations and guidelines , including published tariffs for the transportation of crude oil and refined products . third parties generated 11 percent of the crude oil and refined product shipments on our mpl and orpl common carrier pipelines in 2008 . our mpl and orpl common carrier pipelines transported the volumes shown in the following table for each of the last three years . pipeline barrels handled ( thousands of barrels per day ) 2008 2007 2006 .
what was total pipeline barrels handled ( thousands of barrels per day ) for the three year period?
we also own 176 miles of private crude oil pipelines and 850 miles of private refined products pipelines , and we lease 217 miles of common carrier refined product pipelines . we have partial ownership interests in several pipeline companies that have approximately 780 miles of crude oil pipelines and 3000 miles of refined products pipelines , including about 800 miles operated by mpl . in addition , mpl operates most of our private pipelines and 985 miles of crude oil and 160 miles of natural gas pipelines owned by our e&p segment . our major refined product lines include the cardinal products pipeline and the wabash pipeline . the cardinal products pipeline delivers refined products from kenova , west virginia , to columbus , ohio . the wabash pipeline system delivers product from robinson , illinois , to various terminals in the area of chicago , illinois . other significant refined product pipelines owned and operated by mpl extend from : robinson , illinois , to louisville , kentucky ; garyville , louisiana , to zachary , louisiana ; and texas city , texas , to pasadena , texas. .