Year	%
1995	19.99
1997	19.99
2001	20.49
2002	20.85
2003	23.45
2004	24.84
2005	21.84
2006	22.11
2007	18.23
2008	17.14
2009	18.16
2010	17.71
2011	18.46
2013	19.11
2015	20.98
2016	17.53