Year	%
1987	90.46373
1988	93.1385
1991	93.76883
1992	92.35573
1996	91.65062
1999	95.43926
2000	97.45847
2001	97.64137
2002	97.88123
2003	100
2004	99.60135
2005	99.1712
2006	98.90587
2007	96.0016
2008	97.84071
2009	97.97724
2010	99.53393
2011	97.50071
2012	98.94764
2013	99.1665
2014	98.47366
2015	97.96961
2016	98.54515