administering and litigating product liability claims . litigation defense costs are influenced by a number of factors , including the number and types of cases filed , the number of cases tried annually , the results of trials and appeals , the development of the law controlling relevant legal issues , and litigation strategy and tactics . for further discussion on these matters , see note 18 and item 3 . for the years ended december 31 , 2014 , 2013 and 2012 , product liability defense costs for pm usa were $ 230 million , $ 247 million and $ 228 million , respectively . the factors that have influenced past product liability defense costs are expected to continue to influence future costs . pm usa does not expect future product liability defense costs to be significantly different from product liability defense costs incurred in the last few years . for 2014 , total smokeable products reported shipment volume decreased 2.9% ( 2.9 % ) versus 2013 . pm usa 2019s 2014 reported domestic cigarettes shipment volume decreased 3.0% ( 3.0 % ) , due primarily to the industry 2019s decline , partially offset by retail share gains . when adjusted for trade inventory changes and other factors , pm usa estimates that its 2014 domestic cigarettes shipment volume decreased approximately 3% ( 3 % ) , and that total industry cigarette volumes declined approximately 3.5% ( 3.5 % ) . pm usa 2019s shipments of premium cigarettes accounted for 91.8% ( 91.8 % ) of its reported domestic cigarettes shipment volume for 2014 , versus 92.1% ( 92.1 % ) for 2013 . middleton 2019s reported cigars shipment volume for 2014 increased 6.1% ( 6.1 % ) , driven by black & mild 2019s performance in the tipped cigars segment , including black & mild jazz . marlboro 2019s retail share for 2014 increased 0.1 share point versus 2013 . pm usa grew its total retail share for 2014 by 0.2 share points versus 2013 , driven by marlboro , and l&m in discount , partially offset by share losses on other portfolio brands . in the fourth quarter of 2014 , pm usa expanded distribution of marlboro menthol rich blue to 28 states , primarily in the eastern u.s. , to enhance marlboro 2019s position in the menthol segment . in the machine-made large cigars category , black & mild 2019s retail share for 2014 declined 0.3 share points . in december 2014 , middleton announced the national expansion of black & mild casino , a dark tobacco blend , in the tipped segment . the following discussion compares operating results for the smokeable products segment for the year ended december 31 , 2013 with the year ended december 31 , 2012 . net revenues , which include excise taxes billed to customers , decreased $ 348 million ( 1.6% ( 1.6 % ) ) , due primarily to lower shipment volume ( $ 1046 million ) , partially offset by higher pricing . operating companies income increased $ 824 million ( 13.2% ( 13.2 % ) ) , due primarily to higher pricing ( $ 765 million ) , npm adjustment items ( $ 664 million ) and lower marketing , administration and research costs , partially offset by lower shipment volume ( $ 512 million ) , and higher per unit settlement charges . for 2013 , total smokeable products reported shipment volume decreased 4.1% ( 4.1 % ) versus 2012 . pm usa 2019s 2013 reported domestic cigarettes shipment volume decreased 4.1% ( 4.1 % ) , due primarily to the industry 2019s rate of decline , changes in trade inventories and other factors , partially offset by retail share gains . when adjusted for trade inventories and other factors , pm usa estimated that its 2013 domestic cigarettes shipment volume was down approximately 4% ( 4 % ) , which was consistent with the estimated category decline . pm usa 2019s shipments of premium cigarettes accounted for 92.1% ( 92.1 % ) of its reported domestic cigarettes shipment volume for 2013 , versus 92.7% ( 92.7 % ) for 2012 . middleton 2019s reported cigars shipment volume for 2013 decreased 3.2% ( 3.2 % ) due primarily to changes in wholesale inventories and retail share losses . marlboro 2019s retail share for 2013 increased 0.1 share point versus 2012 behind investments in the marlboro architecture . pm usa expanded marlboro edge distribution nationally in the fourth quarter of 2013 . pm usa 2019s 2013 retail share increased 0.3 share points versus 2012 , due to retail share gains by marlboro , as well as l&m in discount , partially offset by share losses on other portfolio brands . in 2013 , l&m continued to gain retail share as the total discount segment was flat to declining versus 2012 . in the machine-made large cigars category , black & mild 2019s retail share for 2013 decreased 1.0 share point , driven by heightened competitive activity from low-priced cigar brands . smokeless products segment during 2014 , the smokeless products segment grew operating companies income and expanded operating companies income margins . usstc also increased copenhagen and skoal 2019s combined retail share versus 2013 . the following table summarizes smokeless products segment shipment volume performance : shipment volume for the years ended december 31 .
what are the npm adjustment items as a percentage of the operating companies income increase?
smokeless products shipment volume includes cans and packs sold , as well as promotional units , but excludes international volume , which is not material to the smokeless products segment . other includes certain usstc and pm usa smokeless products . new types of smokeless products , as well as new packaging configurations of existing smokeless products , may or may not be equivalent to existing mst products on a can-for-can basis . to calculate volumes of cans and packs shipped , one pack of snus , irrespective of the number of pouches in the pack , is assumed to be equivalent to one can of mst . altria_mdc_2014form10k_nolinks_crops.pdf 31 2/25/15 5:56 pm .