Year	%
1994	19.87
1997	14.62
2001	19.17
2002	19.17
2003	19.36
2004	19.36
2005	19.08
2006	19.36
2007	19.18
2008	19.15
2009	19.15
2010	19.15
2011	19.15
2013	20.03
2014	20.02
2015	12.54