Year	% net
1986	90.74495
1987	93.28087
1988	94.49033
1989	95.49746
1990	94.36834
1991	94.92949
1992	94.85901
1993	94.18651
1994	93.28327
1995	92.01429
1996	91.20545
1997	90.5413
1998	92.33836
1999	94.24575
2000	94.37448
2001	94.44327
2002	94.38307
2003	94.384
2004	94.5025
2005	94.3745
2006	93.96273
2007	95.04578
2008	95.11781
2009	95.41677
2010	95.50824
2011	95.7245
2012	95.70516
2013	95.46902
2014	95.66822
2015	95.90788