Year % of revenue 2005 77.68765996369689 2006 56.78959218979561 2007 37.73707808069371 2008 56.86332561479107 2009 60.11020982722015 2010 63.37455077975829 2011 62.13174889210562 2012 61.327639259770436 2013 57.97895350418687 2014 38.42374604933204 2015 35.31050746093051 2016 34.74631590411139 2017 35.9495456293082 2018 32.63841809290188 2019 31.928630103184098 2020 34.39349328224138 2021 31.23081999095552 2022 29.280483663244013