Year	% net
1986	85.35556
1987	88.82688
1988	90.00475
1989	91.10919
1990	91.75667
1991	92.02427
1992	91.88189
1993	91.55788
1994	90.7771
1995	89.91556
1996	89.39639
1997	88.96357
1998	91.54359
1999	94.1566
2000	94.50614
2001	94.59372
2002	94.6224
2003	94.71622
2004	95.20027
2005	95.3996
2006	94.60974
2007	95.32053
2008	95.87305
2009	96.00264
2010	95.90086
2011	95.95344
2012	96.04665
2013	95.81783
2014	96.06477
2015	96.12652