Year	% net
1986	85.83875
1987	90.03248
1988	91.22523
1989	92.66936
1990	91.70159
1991	92.56609
1992	92.66549
1993	92.05695
1994	91.18124
1995	90.02248
1996	89.45824
1997	88.99475
1998	91.35824
1999	93.81775
2000	93.94684
2001	94.09904
2002	94.148
2003	93.99726
2004	94.19635
2005	93.97271
2006	93.56082
2007	94.82998
2008	94.87012
2009	95.19223
2010	95.51974
2011	95.95529
2012	95.52379
2013	95.47502
2014	95.49944
2015	95.55226