Year	Percent
1969	-0.25517
1970	1.04049
1971	1.90259
1972	0.36931
1973	1.06893
1974	12.40651
1975	8.90659
1976	13.45077
1977	-1.31174
1978	13.43231
1979	17.23432
1980	21.13944
1981	-3.50748
1982	0.6274
1983	-15.34519
1984	-3.94535
1985	-0.96185
1986	2.28375
1987	6.93149
1988	-2.19051
1989	-5.32667
1990	53.94384
1991	-64.99631
1992	28.88938
1993	26.49509
1994	0.75265
1995	-0.96832
1996	7.62557
1997	17.49867
1998	30.71869
1999	14.04677
2000	-1.55092
2001	-0.58956
2002	-9.46722
2003	-34.89767
2004	50.12184
2005	1.72641
2006	7.41602
2007	-1.09528
2008	5.54769
2009	0.67078
2010	3.40014
2011	4.27757
2012	10.28814
2013	4.08594
2014	-2.53028
2015	1.58026
2016	7.75699
2017	-3.55917