Year	Percent
1981	0.6676
1982	3.34452
1983	1.96734
1984	1.2865
1985	-0.5609
1986	-1.03568
1987	-1.30169
1988	-0.30579
1989	-6.00774
1990	2.03716
1991	-8.13594
1992	5.40367
1993	0.0653
1994	-7.94107
1995	0.75133
1996	-3.96489
1997	1.26851
1998	-1.35697
1999	-0.67058
2000	8.08708
2001	-0.15797
2002	-0.11727
2003	-0.29999
2004	-0.47246
2005	0.4164
2006	0.22208
2007	-1.58702
2008	-1.98421
2009	-0.47635
2010	-0.23611
2011	0.14931
2012	0.53851
2013	1.03889
2014	-0.34211
2015	-1.32879
2016	-0.13495
2017	0.194