Year	Percent
1992	7.60739
1993	10.72676
1994	11.14818
1995	9.31501
1996	8.29201
1997	8.94249
1998	6.60022
1999	4.42963
2000	3.03006
2001	2.70277
2002	2.72961
2003	2.04684
2004	1.75798
2005	1.75964
2006	1.68416
2007	1.62921
2008	1.83948
2009	1.80263
2010	1.70263
2011	1.77782
2012	1.69127
2013	1.65649
2014	1.58832
2015	1.5403
2016	1.38459
2017	1.43693