Year	% net
1986	59.28607
1987	59.57025
1988	59.65624
1989	59.38844
1990	59.61357
1991	60.04012
1992	60.4529
1993	60.30259
1994	60.78527
1995	61.57888
1996	62.69985
1997	63.04243
1998	64.33772
1999	64.80337
2000	65.71705
2001	66.64093
2002	67.65336
2003	66.228
2004	67.37197
2005	68.27903
2006	68.75196
2007	69.01169
2008	71.26887
2009	72.20532
2010	72.63742
2011	72.9849
2012	72.76669
2013	76.05959
2014	76.36003
2015	76.75564
2016	77.49153
2017	77.36148
2018	77.50429
