Year	Percent
1992	5.02294
1993	6.22747
1994	7.39141
1995	7.22253
1996	7.03813
1997	6.68644
1998	6.22079
1999	5.26901
2000	4.61043
2001	3.08435
2002	3.33761
2003	3.4591
2004	3.30864
2005	2.04419
2006	1.79271
2007	1.67654
2008	2.09421
2009	3.80004
2010	5.11878
2011	5.87977
2012	7.20469
2013	8.13299
2014	7.81302
2015	7.16294
2016	6.23427
2017	5.18247