Year	% net
1998	62.25701
1999	62.71984
2000	63.67124
2001	64.51425
2002	65.49346
2003	64.15118
2004	65.21038
2005	65.90967
2006	66.12367
2007	66.20655
2008	68.37758
2009	69.51281
2010	70.11992
2011	70.5809
2012	70.61953
2013	74.20864
2014	74.34165
2015	75.07628
2016	75.84929
2017	75.84558
2018	75.98675