Year	% net
1986	58.73349
1987	58.99972
1988	59.05248
1989	58.84244
1990	59.16076
1991	59.17018
1992	59.61712
1993	59.92619
1994	60.40664
1995	61.19699
1996	62.32497
1997	62.73429
1998	63.97495
1999	64.38222
2000	65.21407
2001	66.10622
2002	67.08983
2003	65.52677
2004	66.70741
2005	67.64578
2006	68.15071
2007	68.48382
2008	70.86132
2009	71.89542
2010	72.28398
2011	72.67364
2012	72.45098
2013	75.78636
2014	76.09166
2015	76.47914
2016	77.24594
2017	77.15013
2018	77.29944