Year	Percent
1992	16.70024
1993	17.07177
1994	18.44224
1995	20.56571
1996	19.39501
1997	21.10549
1998	21.05627
1999	21.05718
2000	23.407
2001	19.78441
2002	16.98075
2003	12.6796
2004	14.35209
2005	15.59964
2006	11.36362
2007	11.51721
2008	11.25306
2009	14.70895
2010	16.10011
2011	13.70709
2012	16.17745
2013	12.24906
2014	9.85113
2015	11.57784
2016	12.12123