Year	% net
1977	44.63001
1978	46.20121
1979	49.2368
1982	56.04924
1983	66.56056
1984	66.69595
1985	71.89288
1986	76.0207
1987	73.65971
1989	76.32677
1994	93.44872
1995	94.18347
1997	89.40885
1998	88.21678
1999	87.69795
2000	90.54731
2001	92.21486
2002	91.24346
2003	91.32535
2004	91.96687
2005	93.00856
2006	93.11401
2008	88.59221
2009	87.70018
2010	87.10469
2011	87.1022
2012	85.45677
2013	86.90818
2014	89.06943
2015	91.29455
2016	93.8923
2017	94.42112
2018	93.78209