Year	% net
1986	76.15092
1987	76.58043
1988	76.24913
1989	76.09583
1990	76.04741
1991	77.15752
1992	78.39093
1993	80.8402
1994	82.94498
1995	83.31088
1996	83.78537
1997	83.82258
1998	83.24623
1999	82.85547
2000	83.23357
2001	83.91785
2002	84.4594
2003	85.49364
2004	85.90928
2005	86.5507
2006	86.6115
2007	86.47311
2008	86.89332
2009	87.07373
2010	87.34198
2011	87.62387
2012	87.70007
2013	88.21848
2014	88.56127
2015	89.17572
2016	90.2135
2017	90.31909
2018	90.39525