Year	% net
1998	54.29885
1999	54.75221
2000	55.89123
2001	56.92756
2002	57.97407
2003	59.36224
2004	60.70912
2005	61.97822
2006	62.94343
2007	64.54209
2008	65.79526
2009	66.6165
2010	68.6195
2011	70.6226
2012	71.45665
2013	73.03925
2014	74.10299
2015	74.02076
2016	73.91245
2017	74.4906
2018	74.77997