Year	% net
1970	87.6737
1971	88.93176
1972	94.77855
1974	89.42054
1975	97.29007
1982	98.73396
1983	90.19538
1984	98.89393
1985	96.97644
1986	96.76339
1990	92.29122
1993	92.62748
1998	93.67462
1999	90.47682
2001	98.65596
2004	95.44376
2005	98.81118
2006	98.696
2012	95.84091
2013	95.69563
2015	85.94145