Year	Percent
1960	0.04882
1961	0.80509
1962	0.72162
1963	0.40357
1964	0.05546
1965	-0.40779
1966	-0.75412
1967	-0.6343
1968	-0.42764
1969	-0.8974
1970	-0.88627
1971	-0.4234
1972	-0.15429
1973	0.03093
1974	1.39488
1975	3.80041
1976	2.8441
1977	1.06175
1978	1.07896
1979	1.07199
1980	1.08143
1981	0.86708
1982	0.61133
1983	0.46397
1984	0.38455
1985	0.27354
1986	0.09095
1987	-0.02695
1988	-0.10395
1989	-0.14592
1990	-0.21795
1991	-0.23048
1992	-0.07775
1993	0.12232
1994	0.26909
1995	0.3462
1996	0.376
1997	0.44646
1998	0.50539
1999	0.56563
2000	0.70286
2001	0.70523
2002	0.54767
2003	0.37541
2004	0.23913
2005	0.18553
2006	0.18033
2007	0.1963
2008	0.14419
2009	0.09533
2010	0.04591
2011	-0.14708
2012	-0.40542
2013	-0.54882
2014	-0.53919
2015	-0.41414
2016	-0.31546
2017	-0.30781