Year	Percent
1992	3.9
1996	3.78
2001	6.484
2002	6.833
2003	7.705
2004	5.113
2005	4.937
2007	5.265
2008	4.958
2009	5.888
2010	4.9789
2011	5.3638
2012	5.1682
2013	4.3136
2014	4.1388
2015	4.2482
2016	4.3045
2017	3.8629