Year	% net
1977	50.85929
1991	49.10346
1992	49.3883
1996	54.68437
1997	55.69958
1999	56.60624
2000	55.6689
2001	59.62325
2002	59.60988
2003	56.0829
2009	55.83834
2013	66.9161
2014	72.34108
2015	76.73595
2016	83.16992
2017	85.57232
2018	90.32837