Year	% net
1974	42.5199
1975	44.09006
1998	76.5898
1999	78.473
2000	80.36122
2001	80.92482
2002	80.78871
2003	80.82155
2004	81.42915
2005	81.26323
2006	81.61114
2007	81.83627
2008	83.17861
2009	84.88917
2010	85.80616
2011	87.46214
2012	89.35661
2013	90.11215
2014	90.33155
2015	90.89313
2016	92.18343
2017	93.0542