Year	%
1987	90.22069
1988	93.11972
1991	94.48529
1992	92.20221
1996	90.72837
1999	96.78178
2000	100
2001	100
2002	98.77823
2003	97.96676
2004	100
2005	100
2006	99.59311
2007	95.93273
2008	97.78301
2009	97.63816
2010	99.48823
2011	100
2012	100
2013	100
2014	98.6543
2015	97.66903
2016	98.55613