Year	% net
1998	64.27029
1999	65.49433
2000	65.70281
2001	66.08666
2002	65.46699
2003	66.21249
2004	67.03872
2005	67.31004
2006	68.12956
2007	69.94971
2008	69.8385
2009	71.56113
2010	73.33647
2011	74.67501
2012	73.46922
2013	75.43998
2014	77.67077
2015	77.24413
2016	77.24496
2017	76.92976
2018	76.79316