Year	Percent
1996	5.7191
1997	5.2184
1998	6.272
1999	6.1215
2000	5.7178
2001	4.2009
2002	4.9329
2003	5.3668
2004	5.2714
2005	5.1567
2006	4.3492
2007	3.4201
2008	3.2599
2009	5.3088
2010	7.1107
2011	7.6499
2012	7.5702
2013	8.9008
2014	8.2848
2015	7.3022
2016	6.8877
2017	5.185