Year	% net
1998	66.22071
1999	66.66902
2000	67.51834
2001	68.51491
2002	69.59586
2003	67.99845
2004	69.24023
2005	70.37555
2006	71.12619
2007	71.58807
2008	74.01598
2009	74.79004
2010	75.03588
2011	75.29258
2012	74.79326
2013	77.82527
2014	78.33547
2015	78.38621
2016	79.11001
2017	78.84201
2018	78.98677