2011 compared to 2010 mfc 2019s net sales for 2011 increased $ 533 million , or 8% ( 8 % ) , compared to 2010 . the increase was attributable to higher volume of about $ 420 million on air and missile defense programs ( primarily pac-3 and thaad ) ; and about $ 245 million from fire control systems programs primarily related to the sof clss program , which began late in the third quarter of 2010 . partially offsetting these increases were lower net sales due to decreased volume of approximately $ 75 million primarily from various services programs and approximately $ 20 million from tactical missile programs ( primarily mlrs and jassm ) . mfc 2019s operating profit for 2011 increased $ 96 million , or 10% ( 10 % ) , compared to 2010 . the increase was attributable to higher operating profit of about $ 60 million for air and missile defense programs ( primarily pac-3 and thaad ) as a result of increased volume and retirement of risks ; and approximately $ 25 million for various services programs . adjustments not related to volume , including net profit rate adjustments described above , were approximately $ 35 million higher in 2011 compared to 2010 . backlog backlog increased in 2012 compared to 2011 mainly due to increased orders and lower sales on fire control systems programs ( primarily lantirn ae and sniper ae ) and on various services programs , partially offset by lower orders and higher sales volume on tactical missiles programs . backlog increased in 2011 compared to 2010 primarily due to increased orders on air and missile defense programs ( primarily thaad ) . trends we expect mfc 2019s net sales for 2013 will be comparable with 2012 . we expect low double digit percentage growth in air and missile defense programs , offset by an expected decline in volume on logistics services programs . operating profit and margin are expected to be comparable with 2012 results . mission systems and training our mst business segment provides surface ship and submarine combat systems ; sea and land-based missile defense systems ; radar systems ; mission systems and sensors for rotary and fixed-wing aircraft ; littoral combat ships ; simulation and training services ; unmanned technologies and platforms ; ship systems integration ; and military and commercial training systems . mst 2019s major programs include aegis , mk-41 vertical launching system ( vls ) , tpq-53 radar system , mh-60 , lcs , and ptds . mst 2019s operating results included the following ( in millions ) : .

2012: net sales: 7579
operating profit: 737
operating margins: -9.7
backlog at year-end: 10700
2011: net sales: 7132
operating profit: 645
operating margins: -9
backlog at year-end: 10500
2010: net sales: 7443
operating profit: 713
operating margins: -9.6
backlog at year-end: 10600

2012 compared to 2011 mst 2019s net sales for 2012 increased $ 447 million , or 6% ( 6 % ) , compared to 2011 . the increase in net sales for 2012 was attributable to higher volume and risk retirements of approximately $ 395 million from ship and aviation system programs ( primarily ptds ; lcs ; vls ; and mh-60 ) ; about $ 115 million for training and logistics solutions programs primarily due to net sales from sim industries , which was acquired in the fourth quarter of 2011 ; and approximately $ 30 million as a result of increased volume on integrated warfare systems and sensors programs ( primarily aegis ) . partially offsetting the increases were lower net sales of approximately $ 70 million from undersea systems programs due to lower volume on an international combat system program and towed array systems ; and about $ 25 million due to lower volume on various other programs . mst 2019s operating profit for 2012 increased $ 92 million , or 14% ( 14 % ) , compared to 2011 . the increase was attributable to higher operating profit of approximately $ 175 million from ship and aviation system programs , which reflects higher volume and risk retirements on certain programs ( primarily vls ; ptds ; mh-60 ; and lcs ) and reserves of about $ 55 million for contract cost matters on ship and aviation system programs recorded in the fourth quarter of 2011 ( including the terminated presidential helicopter program ) . partially offsetting the increase was lower operating profit of approximately $ 40 million from undersea systems programs due to reduced profit booking rates on certain programs and lower volume on an international combat system program and towed array systems ; and about $ 40 million due to lower volume on various other programs . adjustments not related to volume , including net profit booking rate adjustments and other matters described above , were approximately $ 150 million higher for 2012 compared to 2011. .

Questions:
what was the operating profit for mst in 2011?
and what was it in 2010?
what was, then, the change over the year?
and how much does this change represent in relation to that operating profit in 2010?

Answers:
645
713
-68
-9.5%