Year % net 1999 60.90379 2000 62.29479 2001 60.86982 2002 60.42583 2003 63.7075 2004 62.68135 2005 68.03964 2006 68.6966 2007 76.97758 2008 79.70525 2009 82.4496 2010 82.5328 2011 81.23662 2012 80.93965 2013 80.11243 2015 80.79577 2016 78.60232 2017 80.81903 2018 81.31252