Year	%
1991	90.15486
1999	81.07095
2000	78.61395
2001	91.04242
2002	89.82003
2003	87.79623
2007	87.86108
2012	85.94196
2013	88.12634
2014	88.31792
2015	88.94784
2016	84.06958