Year	Percent
1960	0.87302
1961	-3.02409
1962	-3.07258
1963	-2.15661
1964	0.35308
1965	1.27346
1966	-0.4122
1967	-2.27037
1968	-1.57052
1969	-0.45457
1970	-3.94236
1971	-2.7726
1972	-0.64896
1973	-1.26931
1974	-0.63596
1975	-10.87309
1976	-18.81434
1977	-20.42523
1978	-13.69747
1979	-12.85447
1980	-8.6702
1981	-12.09363
1982	-12.13079
1983	-7.1047
1984	-9.09432
1985	-8.28862
1986	-6.51587
1987	-4.695
1988	-0.14451
1989	-5.24097
1990	-5.50805
1991	-5.14176
1992	-5.91901
1993	-5.54695
1994	-5.43655
1995	-6.36859
1996	-3.42359
1997	-3.30192
1998	-3.99007
1999	-3.67796
2000	-5.58696
2001	-2.99967
2002	-2.69886
2003	-3.32019
2004	-5.38134
2005	-6.07654
2006	-5.98557
2007	-9.34381
2008	-14.18812
2009	-11.90875
2010	-10.7816
2011	-14.02673
2012	-15.26582
2013	-14.46527
2014	-12.5118
2015	-7.7907
2016	-10.24034
2017	-9.90499