Year	Percent
1996	2.65036
1997	2.43121
1998	2.74837
1999	2.66901
2000	2.80068
2001	2.21234
2002	2.38275
2003	2.4124
2004	2.14491
2005	2.24297
2006	1.8574
2007	1.38172
2008	1.27955
2009	1.71646
2010	2.77152
2011	2.83885
2012	2.94738
2013	3.55679
2014	3.36898
2015	2.92608
2016	2.73711
2017	2.07892