Year	Percent
1992	0.40149
1993	5.43124
1994	3.10435
1995	4.73243
1996	5.40518
1997	5.9614
1998	5.20166
1999	9.40678
2000	7.49247
2001	12.71549
2002	10.50669
2003	8.0537
2004	13.01286
2005	4.45711
2006	9.39605
2007	11.41903
2008	12.60393
2009	12.38059
2010	5.03631
2011	7.14351
2012	6.56165
2013	4.2307
2014	3.26293
2015	3.45978
2016	12.22303
2017	2.84952