Year % net 2002 44.56638 2003 47.51588 2004 51.92799 2005 54.86775 2006 53.48415 2007 58.72754 2008 59.20603 2009 60.11687 2010 60.55766 2011 58.12014 2012 58.22598 2013 57.63688 2014 60.37147 2015 55.94829 2016 59.97299 2017 59.84739 2018 61.56655