Year	% net
1998	59.5732
1999	60.77511
2000	61.73821
2001	62.66023
2002	63.0966
2003	64.88938
2004	66.88209
2005	68.26656
2006	69.60457
2007	71.78609
2008	71.90295
2009	73.878
2010	75.90492
2011	77.55059
2012	77.4789
2013	78.29122
2014	80.91952
2015	80.78122
2016	80.9557
2017	80.73113
2018	81.24246