Year	Percent
1992	2.81907
1993	4.72285
1994	2.66912
1995	2.88719
1996	2.71803
1997	2.01279
1998	1.66265
1999	1.20653
2000	3.93718
2001	5.10496
2002	3.04391
2003	3.09793
2004	4.66564
2005	3.21723
2006	3.6156
2007	6.09546
2008	9.7277
2009	11.16018
2010	9.1399
2011	8.13046
2012	7.45397
2013	9.81721
2014	8.69001
2015	8.68785
2016	8.78673
2017	7.83883