Year % net 1999 53.18786 2000 54.84529 2001 53.97559 2002 52.98472 2003 56.58969 2004 63.90916 2005 61.57834 2006 61.27996 2007 71.65181 2008 77.02734 2009 80.17601 2010 82.10624 2011 79.89336 2012 79.72333 2013 79.63795 2015 81.5955 2016 76.91772 2017 79.77105 2018 80.91649