Year	Percent
1995	87.78202
1996	87.77313
1997	71.27156
1998	72.54457
1999	73.18487
2000	87.26372
2001	87.38328
2002	87.33186
2003	87.28223
2004	87.44678
2005	87.98337
2006	87.96517
2007	88.02851
2008	88.00591
2009	87.57926
2010	86.99948
2011	86.94974
2012	87.17314
2013	87.24176
2014	87.27674
2015	87.47746
2016	87.13136
2017	87.00975