Year	Percent
1999	6.64
2000	7.17
2001	7.76
2002	7.58
2003	2.39
2004	1.03
2005	1.11
2006	2.93
2007	2.33
2008	2.38
2009	2.56
2010	2.66
2011	3.08
2012	2.34
2013	2.15
2014	2.41
2015	4.36
2016	4.63
2017	3.76