Year	% net
1996	82.52305
1997	83.23231
1998	82.86775
1999	84.06819
2000	85.03263
2001	86.357
2002	87.33135
2003	87.59414
2004	87.24472
2005	87.99967
2006	88.21168
2007	88.64418
2008	89.23788
2009	89.26189
2010	89.43946
2011	89.24446
2012	89.11786
2013	90.11011
2014	89.87666
2015	90.22955
2016	89.96548
2017	90.0945
2018	90.06636