Year	Percent
1990	0.00003
1991	0.13794
1992	0.30651
1993	0.35656
1994	1.13385
1995	1.11252
1996	0.70731
1997	3.3902
1998	4.83848
1999	2.87704
2000	2.76987
2001	2.84158
2002	2.47755
2003	3.08012
2004	8.45356
2005	6.51836
2006	8.90986
2007	5.74256
2008	6.39864
2009	2.68677
2010	1.92834
2011	1.28553
2012	1.7753
2013	2.01245
2014	1.93951
2015	2.4269
2016	3.32899
2017	2.33693