Year	% net
1998	49.73541
1999	50.08662
2000	51.08576
2001	51.76041
2002	52.37108
2003	53.23577
2004	54.1322
2005	54.82988
2006	55.49902
2007	56.57491
2008	57.35668
2009	57.85632
2010	59.25592
2011	60.37714
2012	60.68411
2013	61.91644
2014	62.72301
2015	62.75054
2016	62.8315
2017	63.24158
2018	63.32784