Year	% net
1992	93.5704
1993	92.20265
1994	91.78379
1995	90.82041
1996	91.06347
1997	90.27319
1998	90.29027
1999	90.68015
2000	89.91657
2001	90.71911
2002	91.76248
2003	93.71363
2004	93.3452
2005	91.89726
2006	92.08733
2007	92.30501
2008	92.55366
2009	92.21762
2010	92.9478
2011	93.13939
2012	92.91753
2013	93.35407
2014	93.21996
2015	93.54765
2016	93.69839
2017	91.79124
2018	91.67335