Year	Percent
1996	3.51129
1997	3.7865
1998	3.5119
1999	4.00595
2000	5.15394
2001	4.02757
2002	4.20995
2003	3.44791
2004	2.97316
2005	2.39792
2006	2.30352
2007	2.41147
2008	2.25668
2009	2.28617
2010	2.21067
2011	2.12401
2012	2.09517
2013	2.02069
2014	2.06594
2015	1.94872
2016	1.88144
2017	1.8285