Year	%
1984	86.8628
1985	89.58164
1986	88.77966
1987	88.19542
1988	87.86187
1989	87.37392
1990	83.21059
1991	83.23124
1992	82.91582
1993	83.47584
1994	83.98344
1995	84.66208
1996	85.27614
1997	86.36219
1998	87.44519
1999	87.97297
2000	89.97097
2001	87.36964
2002	89.44458
2003	90.35883
2004	90.14575
2005	91.02352
2007	94.86459
2008	93.37846
2009	95.64019
2010	95.00854
2011	94.3839
2012	93.59977
2013	95.69669
2014	93.82857
2015	93.53939
2016	93.22067
2017	94.30178