Year	% net
1981	90.34744
1984	90.35065
1992	89.24923
1993	89.52996
1994	85.89953
1999	70.7111
2004	79.4314
2005	82.12592
2006	83.14323
2007	85.49348
2008	84.04865
2009	81.54506
2010	79.75847
2011	74.73581
2012	75.71744
2013	68.50649
2014	72.62728
2015	58.91371
2016	66.65546
2017	65.13657
2018	62.4958