Year	% net
1986	86.5428
1987	90.43156
1988	91.59573
1989	92.94616
1990	91.90022
1991	92.68461
1992	92.81055
1993	92.27616
1994	91.45535
1995	90.36408
1996	89.83247
1997	89.36705
1998	91.55294
1999	93.85666
2000	94.00152
2001	94.09031
2002	94.12122
2003	94.01758
2004	94.19893
2005	94.01109
2006	93.63552
2007	94.84807
2008	94.90434
2009	95.23213
2010	95.5121
2011	95.94855
2012	95.52392
2013	95.45252
2014	95.47628
2015	95.58924