Year	Percent
1987	1.3534
1988	11.21962
1989	0.66356
1990	3.68801
1991	-9.34573
1992	-14.87656
1993	-15.48366
1994	-20.05684
1995	-6.36328
1996	5.51123
1997	8.32369
1998	0.5672
1999	2.12678
2000	4.17836
2001	4.32696
2002	-0.93089
2003	5.914
2004	5.73953
2005	-1.29511
2006	2.00043
2007	7.51274
2008	7.37644
2009	1.65165
2010	-1.65175
2011	4.67472
2012	-1.73814
2013	8.73579
2014	1.958
2015	1.75886
2016	2.23181
2017	2.5262