Year	Percent
1988	0.20264
1989	0.24951
1990	-0.56278
1991	0.08901
1992	0.31018
1993	0.64243
1994	1.64337
1995	0.09219
1996	0.15154
1997	0.03969
1998	0.21939
1999	0.75748
2000	0.79908
2001	0.02198
2002	0.00108
2003	3.04214
2004	3.94676
2005	3.36111
2006	4.01284
2007	3.45073
2008	3.37554
2009	3.17324
2010	1.26667
2011	2.33719
2012	2.34836
2013	4.29367
2014	2.59381
2015	1.33486
2016	2.02574
2017	2.05326