Year	% net
1971	86.85752
1972	88.05772
1974	90.53286
1976	86.89338
1977	91.75515
1979	88.68043
1982	88.87672
1991	91.87291
1992	89.64668
1993	88.06664
1995	89.89822
1996	88.43708
2003	91.33466
2008	92.743
2009	88.01357
2010	91.70702
2011	93.15013
2012	93.09037