Year	% net
1977	78.01196
1993	95.98406
1994	97.97036
1995	99.04244
1996	97.67064
1999	93.58057
2000	93.23441
2001	94.11793
2002	94.64411
2003	96.34794
2004	97.69044
2005	97.54728
2006	97.9871
2007	96.35917
2008	94.63375
2009	93.46701
2010	92.69016
2011	92.56495
2012	93.15346
2013	93.63938
2014	93.83306
2015	93.65346
2016	94.11758
2017	94.94691