Year	Percent
1998	6.4907
2000	5.501
2001	9.7082
2002	6.5426
2003	16.2764
2004	11.0205
2005	6.4584
2006	5.0904
2007	3.3689
2008	4.5836
2009	8.8002
2010	12.1197
2011	11.0101
2012	10.483
2013	8.7005
2014	7.9406
2015	7.1418
2016	6.478
2017	6.3797