Year	% net
1998	19.71152
1999	19.99889
2000	20.69953
2001	21.53225
2002	22.50022
2003	23.40669
2004	24.60959
2005	25.51868
2006	26.34444
2007	27.27121
2008	28.9109
2009	30.2005
2010	31.70727
2011	32.06235
2012	32.45156
2013	33.38244
2014	34.02056
2015	34.80147
2016	35.06753
2017	35.28772
2018	35.58147