Year	Percent
1987	0.38826
1988	2.98964
1989	0.11469
1990	-0.34622
1991	-2.75097
1992	-2.60412
1993	-0.88609
1994	-1.28133
1995	0.26342
1996	1.1042
1997	2.59008
1998	1.62922
1999	2.00692
2000	0.70196
2001	1.77964
2002	3.25169
2003	-0.62744
2004	0.39494
2005	0.98073
2006	-0.88498
2007	4.54952
2008	1.85261
2009	-3.30371
2010	2.51297
2011	3.30561
2012	3.60452
2013	1.63614
2014	1.34531
2015	1.35922
2016	7.74182
2017	5.51532