Year	Percent
1960	0.87142
1961	2.99237
1962	1.10373
1963	1.02883
1964	1.05291
1965	1.00347
1966	0.92645
1967	0.85094
1968	0.77347
1969	0.77072
1970	0.43318
1971	0.42275
1972	0.85586
1973	0.97041
1974	1.03265
1975	1.04961
1976	1.05792
1977	1.05907
1978	1.01996
1979	0.99395
1980	0.82353
1981	0.7261
1982	0.77437
1983	0.72675
1984	0.68746
1985	0.67395
1986	0.61938
1987	0.55684
1988	0.53003
1989	0.48156
1990	0.43962
1991	0.07747
1992	0.03247
1993	0.38172
1994	0.39405
1995	0.29263
1996	0.21167
1997	0.18463
1998	0.13412
1999	0.10205
2000	-0.13538
2001	-0.18301
2002	-0.03635
2003	-0.06582
2004	-0.02036
2005	0.00981
2006	0.0046
2007	0.02918
2008	0.08576
2009	0.13326
2010	0.09319
2011	0.12894
2012	0.17018
2013	0.10746
2014	0.09705
2015	0.09503
2016	0.12892
2017	0.16731