Year	% net
1981	92.27485
1982	94.20892
1983	99.05795
1984	98.73902
1985	100
1986	100
1990	97.30896
2000	89.26997
2001	90.22427
2002	97.46535
2003	95.94187
2004	94.24963
2005	91.79219
2006	94.16778
2007	93.2892
2015	94.16119
2016	94.85034
2017	94.86626
2018	95.39814