Year % net 1998 79.90135 1999 80.73788 2000 82.29494 2001 84.02187 2002 84.04544 2003 84.33615 2004 82.66045 2005 81.56678 2006 82.22103 2007 82.961 2008 83.00859 2009 82.76428 2010 84.57692 2011 86.04322 2012 86.51647 2013 88.44553 2014 89.01402 2015 89.26089 2016 88.53747 2017 88.96116 2018 88.43456