Year	Percent
1986	9.33
1987	8.13
1992	8.13
1996	9.77
2001	15.712
2002	16.116
2003	15.058
2004	14.45
2005	12.481
2007	12.256
2008	12.029
2009	13.131
2010	11.657
2011	10.7401
2012	10.5792
2013	9.6551
2014	9.1608
2015	9.1352
2016	9.6667
2017	9.9994