Year	% net
1998	52.35304
1999	52.62062
2000	53.55724
2001	53.93872
2002	54.23751
2003	54.81026
2004	55.56869
2005	56.0672
2006	56.63314
2007	57.67008
2008	58.32066
2009	58.60157
2010	59.82508
2011	60.73689
2012	60.73457
2013	62.06855
2014	62.80906
2015	62.81141
2016	62.88144
2017	63.25115
2018	63.41804