Year	% net
1998	66.13697
1999	66.55758
2000	67.33614
2001	68.3239
2002	69.34028
2003	67.6684
2004	68.9402
2005	70.11426
2006	70.91648
2007	71.43501
2008	73.91372
2009	74.72147
2010	74.92335
2011	75.18047
2012	74.66772
2013	77.69926
2014	78.20254
2015	78.21257
2016	78.93966
2017	78.71033
2018	78.86107