Year	Percent
1992	0.77527
1993	1.2951
1994	1.82486
1995	2.03603
1996	2.23316
1997	2.03344
1998	1.63233
1999	1.42094
2000	1.26858
2001	1.36656
2002	1.36687
2003	1.98645
2004	2.16246
2005	2.73802
2006	2.81554
2007	2.9238
2008	2.63394
2009	3.11548
2010	3.96544
2011	3.94571
2012	4.86068
2013	5.49991
2014	4.85248
2015	4.13158
2016	3.45648
2017	2.8535