Year	% net
1983	86.57582
1984	86.83343
1985	88.34618
1986	88.76574
1987	87.92619
1991	92.01323
1992	93.94963
1993	94.63315
1994	93.01187
1995	92.52999
1996	92.04451
1997	92.20082
2005	97.34989
2006	99.71355
2007	98.25451
2008	99.41225
2009	99.37709
2010	99.54073
2011	99.39812
2012	99.24681
2013	99.49267
2014	96.62933
2015	99.45328
2016	99.60035
2017	99.3775