Year	Percent
1960	-2.39975
1961	-1.67514
1962	-1.88623
1963	-1.64716
1964	-1.98363
1965	-1.9274
1966	-2.55993
1967	-1.93603
1968	-0.91683
1969	-0.32298
1970	-0.09959
1971	-0.34125
1972	0.31958
1973	-0.52297
1974	-1.20556
1975	-1.01457
1976	0.57395
1977	0.11551
1978	-0.28041
1979	-1.43962
1980	-3.14396
1981	-2.66833
1982	-2.18717
1983	-2.04148
1984	-1.46262
1985	-2.42089
1986	-1.85047
1987	-1.39453
1988	-1.43965
1989	-1.15297
1990	-1.41962
1991	-0.00462
1992	-0.76117
1993	0.01085
1994	-0.3116
1995	-1.19952
1996	-1.17864
1997	-1.25852
1998	-1.68803
1999	-1.94002
2000	-0.92478
2001	-0.89422
2002	-0.99985
2003	-0.71384
2004	-1.81677
2005	-2.83657
2006	-3.26363
2007	-4.14348
2008	-5.22851
2009	-5.54591
2010	-4.508
2011	-6.54306
2012	-6.72486
2013	-2.98241
2014	-2.98626
2015	-2.29783
2016	-1.71933
2017	-2.90724