Year	Percent
1993	3.423
1994	3.58
1995	3.402
1996	3.291
1997	3.5945
1998	4.5848
1999	7.169
2000	7.3305
2001	6.6884
2002	5.7917
2003	5.8514
2004	7.0586
2005	6.4548
2006	5.8132
2007	4.2222
2008	3.4605
2009	5.8477
2010	6.382
2011	5.7987
2012	6.0234
2013	5.9027
2014	5.0985
2015	4.232
2016	3.3782
2017	2.3371