{"pre_text": ["$ 15 million for fire control programs due to increased deliveries ( primarily apache ) , partially offset by lower risk retirements ( primarily sniper ae ) .", "adjustments not related to volume , including net profit booking rate adjustments and other matters , were approximately $ 95 million lower for 2014 compared to 2013 .", "backlog backlog increased in 2015 compared to 2014 primarily due to higher orders on pac-3 , lantirn/sniper and certain tactical missile programs , partially offset by lower orders on thaad .", "backlog decreased in 2014 compared to 2013 primarily due to lower orders on thaad and fire control systems programs , partially offset by higher orders on certain tactical missile programs and pac-3 .", "trends we expect mfc 2019s net sales to be flat or experience a slight decline in 2016 as compared to 2015 .", "operating profit is expected to decrease by approximately 20 percent , driven by contract mix and fewer risk retirements in 2016 compared to 2015 .", "accordingly , operating profit margin is expected to decline from 2015 levels .", "mission systems and training as previously described , on november 6 , 2015 , we acquired sikorsky and aligned the sikorsky business under our mst business segment .", "the results of the acquired sikorsky business have been included in our financial results from the november 6 , 2015 acquisition date through december 31 , 2015 .", "as a result , our consolidated operating results and mst business segment operating results for the year ended december 31 , 2015 do not reflect a full year of sikorsky operations .", "our mst business segment provides design , manufacture , service and support for a variety of military and civil helicopters , ship and submarine mission and combat systems ; mission systems and sensors for rotary and fixed-wing aircraft ; sea and land-based missile defense systems ; radar systems ; the littoral combat ship ( lcs ) ; simulation and training services ; and unmanned systems and technologies .", "in addition , mst supports the needs of customers in cybersecurity and delivers communication and command and control capabilities through complex mission solutions for defense applications .", "mst 2019s major programs include black hawk and seahawk helicopters , aegis combat system ( aegis ) , lcs , space fence , advanced hawkeye radar system , and tpq-53 radar system .", "mst 2019s operating results included the following ( in millions ) : ."], "post_text": ["2015 compared to 2014 mst 2019s net sales in 2015 increased $ 359 million , or 4% ( 4 % ) , compared to 2014 .", "the increase was attributable to net sales of approximately $ 400 million from sikorsky , net of adjustments required to account for the acquisition of this business in the fourth quarter of 2015 ; and approximately $ 220 million for integrated warfare systems and sensors programs , primarily due to the ramp-up of recently awarded programs ( space fence ) .", "these increases were partially offset by lower net sales of approximately $ 150 million for undersea systems programs due to decreased volume as a result of in-theater force reductions ( primarily persistent threat detection system ) ; and approximately $ 105 million for ship and aviation systems programs primarily due to decreased volume ( merlin capability sustainment program ) .", "mst 2019s operating profit in 2015 decreased $ 92 million , or 10% ( 10 % ) , compared to 2014 .", "operating profit decreased by approximately $ 75 million due to performance matters on an international program ; approximately $ 45 million for sikorsky due primarily to intangible amortization and adjustments required to account for the acquisition of this business in the fourth quarter of 2015 ; and approximately $ 15 million for integrated warfare systems and sensors programs , primarily due to investments made in connection with a recently awarded next generation radar technology program , partially offset by higher risk retirements ( including halifax class modernization ) .", "these decreases were partially offset by approximately $ 20 million in increased operating profit for training and logistics services programs , primarily due to reserves recorded on certain programs in 2014 that were not repeated in 2015 .", "adjustments not related to volume , including net profit booking rate adjustments and other matters , were approximately $ 100 million lower in 2015 compared to 2014. ."], "table": [["", "2015", "2014", "2013"], ["net sales", "$ 9091", "$ 8732", "$ 9037"], ["operating profit", "844", "936", "1065"], ["operating margins", "9.3% ( 9.3 % )", "10.7% ( 10.7 % )", "11.8% ( 11.8 % )"], ["backlog at year-end", "$ 30100", "$ 13300", "$ 12600"]], "table_ori": [["", "2015", "2014", "2013"], ["Net sales", "$9,091", "$8,732", "$9,037"], ["Operating profit", "844", "936", "1,065"], ["Operating margins", "9.3%", "10.7%", "11.8%"], ["Backlog at year-end", "$30,100", "$13,300", "$12,600"]]}

Question: what were average net sales for mst in millions from 2013 to 2015?
Evidence:
table_1: the net sales of 2015 is $ 9091 ; the net sales of 2014 is $ 8732 ; the net sales of 2013 is $ 9037 ;
Program: table_average(net sales, none)
Answer:
str_answer: 8953
exe_answer: 8953.33333