Year	Percent
1992	2.52964
1993	3.72607
1994	3.59501
1995	3.83035
1996	3.76661
1997	3.13392
1998	3.10886
1999	2.45932
2000	2.3875
2001	2.02451
2002	1.96708
2003	1.90453
2004	1.88258
2005	2.24898
2006	2.31691
2007	2.33795
2008	2.49911
2009	3.17339
2010	3.99829
2011	3.61745
2012	3.78583
2013	3.48354
2014	2.63925
2015	2.31556
2016	1.80152
2017	1.28736