Year	Percent
1960	0.90188
1961	0.5921
1962	0.59529
1963	0.8273
1964	0.93215
1965	1.039
1966	1.25007
1967	1.16825
1968	0.88496
1969	0.54575
1970	0.64076
1971	0.77639
1972	0.79632
1973	0.82207
1974	0.53263
1975	0.97762
1976	1.47591
1977	1.20833
1978	1.08889
1979	1.07078
1980	0.98925
1981	0.27396
1982	0.19927
1983	0.62552
1984	0.51021
1985	0.4898
1986	1.24492
1987	1.20394
1988	0.27202
1989	0.05787
1990	0.09062
1991	0.06344
1992	-0.1467
1993	-0.2383
1994	-0.11569
1995	0.02156
1996	-0.06254
1997	-0.13445
1998	-0.21812
1999	0.07143
2000	0.29607
2001	0.1575
2002	0.12392
2003	0.0603
2004	0.06407
2005	0.17321
2006	0.31911
2007	0.55921
2008	0.15814
2009	0.90388
2010	0.43608
2011	0.20773
2012	0.21002
2013	0.13573
2014	0.09835
2015	0.07519
2016	0.0732
2017	0.08258