Year	Percent
1983	0.44209
1984	1.07193
1985	4.24329
1986	0.9453
1987	0.65824
1988	4.15423
1989	4.55071
1990	2.14285
1991	2.08928
1992	2.11705
1993	3.08234
1994	3.67295
1995	3.29496
1996	5.04686
1997	6.56765
1998	6.93582
1999	12.20048
2000	17.38834
2001	6.72879
2002	3.33666
2003	5.07891
2004	7.94439
2005	13.22124
2006	19.80025
2007	14.01897
2008	5.46286
2009	8.25551
2010	12.69396
2011	6.19398
2012	8.12803
2013	1.82229
2014	1.62952
2015	18.84697
2016	12.64723
2017	-2.62243