Year	Percent
1960	0.73572
1961	1.03527
1962	1.79859
1963	1.88686
1964	1.73332
1965	1.57819
1966	1.04138
1967	1.06106
1968	1.55011
1969	1.61415
1970	1.50219
1971	1.81432
1972	0.21755
1973	-0.54171
1974	0.97473
1975	0.52306
1976	0.18089
1977	0.04015
1978	-0.75084
1979	-0.33087
1980	0.12843
1981	0.3964
1982	0.98551
1983	0.70239
1984	0.51534
1985	0.50615
1986	-0.03209
1987	-0.79312
1988	-1.46456
1989	-1.56456
1990	-1.05154
1991	-0.68806
1992	-0.3406
1993	0.26855
1994	0.22912
1995	0.35131
1996	0.80084
1997	0.44329
1998	-1.70475
1999	-3.55374
2000	-4.07539
2001	-3.66178
2002	0.12236
2003	2.0621
2004	1.72503
2005	2.55007
2006	2.56811
2007	1.97486
2008	1.25823
2009	0.65115
2010	1.26551
2011	1.4209
2012	0.82993
2013	1.13368
2014	1.34764
2015	1.31959
2016	1.05969
2017	0.8426