Year % net 1992 14.44277 1993 14.45191 1994 14.48769 1995 14.68136 1996 14.63327 1997 14.58592 1998 14.93036 1999 15.18335 2000 15.80981 2001 16.65368 2002 17.42858 2003 18.32195 2004 19.42887 2005 20.13448 2006 20.68107 2007 21.12581 2008 23.28003 2009 24.93558 2010 26.74966 2011 27.02615 2012 27.39594 2013 28.61577 2014 29.23948 2015 30.08896 2016 30.80293 2017 31.79068 2018 32.19886