Year	Percent
1960	1.25445
1961	1.26125
1962	1.25549
1963	1.21868
1964	1.14152
1965	1.03849
1966	0.92447
1967	0.82436
1968	0.75387
1969	0.72496
1970	0.72489
1971	0.73433
1972	0.7335
1973	0.71768
1974	0.67911
1975	0.62515
1976	0.56745
1977	0.51756
1978	0.4776
1979	0.45201
1980	0.43633
1981	0.50342
1982	0.32404
1983	0.35662
1984	0.37506
1985	0.32064
1986	0.35289
1987	0.38285
1988	0.44352
1989	0.48793
1990	0.22959
1991	0.20881
1992	0.28765
1993	0.05549
1994	-0.496
1995	-0.79035
1996	-0.88742
1997	-0.91113
1998	-0.89374
1999	-0.94291
2000	-1.0066
2001	-1.00549
2002	-0.99368
2003	-0.81144
2004	-0.75863
2005	-0.73279
2006	-0.67609
2007	-0.5968
2008	-0.54146
2009	-0.44393
2010	-0.39729
2011	-0.35948
2012	-0.2471
2013	-0.2277
2014	-0.47962
2015	-0.26081
2016	-0.33138
2017	-0.38623