Year	Percent
1970	0.13687
1971	-1.551
1972	0.34951
1973	-4.18744
1974	-8.21879
1975	3.9871
1976	-0.61963
1977	1.05538
1978	0.69264
1979	-1.13581
1980	-1.94012
1981	3.526
1982	7.26211
1983	3.82739
1984	4.05423
1985	0.47299
1986	1.11076
1987	-1.36918
1988	-0.37165
1989	-0.68523
1990	1.58236
1991	0.12101
1992	-0.05758
1993	1.02822
1994	0.25843
1995	-1.30782
1996	-0.71061
1997	1.83141
1998	2.91838
1999	-0.48166
2000	-0.99257
2001	0.01067
2002	-0.3239
2003	-0.27177
2004	-0.12921
2005	3.68592
2006	4.86007
2007	5.84997
2008	7.59063
2009	8.49635
2010	5.53433
2011	2.42958
2012	1.65527
2013	1.18727
2014	1.05927
2015	1.24429
2016	1.15555
2017	0.20784