Year	% net
1991	18.64144
1992	18.64056
1993	18.70485
1994	19.02731
1995	19.70813
1996	19.95738
1997	20.22982
1998	20.75196
1999	20.98226
2000	22.02342
2001	22.48416
2002	22.76338
2003	24.4589
2004	25.94718
2005	26.71143
2006	27.65909
2007	28.22813
2008	29.46092
2009	30.42637
2010	31.18536
2011	31.6387
2012	32.3911
2013	31.58323
2014	31.90347
2015	32.57299
2016	32.92023
2017	33.77905
2018	33.78372