Year	Percent
1997	5.50161
1999	2.28304
2000	4.72663
2001	10.39873
2002	1.62245
2003	1.40903
2004	1.24612
2005	0.61918
2006	1.0804
2007	0.87587
2008	1.40588
2009	2.1819
2010	1.84866
2011	2.59836
2012	2.64941
2013	2.88315
2014	2.70033
2015	5.27428
2016	5.93861