Year	Percent
1960	2.80967
1961	-0.11855
1962	0.18232
1963	0.39087
1964	0.47065
1965	0.46395
1966	0.43497
1967	0.41081
1968	0.34698
1969	0.23065
1970	0.53465
1971	1.84261
1972	1.67747
1973	1.50741
1974	1.39001
1975	1.25674
1976	1.17663
1977	1.04326
1978	0.84664
1979	0.51323
1980	0.11413
1981	-0.2836
1982	-0.61327
1983	-0.89297
1984	-1.05468
1985	-1.11092
1986	-1.17307
1987	-1.17862
1988	-0.93862
1989	-0.41529
1990	0.33491
1991	1.019
1992	0.57647
1993	1.10599
1994	1.42746
1995	1.52342
1996	1.59115
1997	1.65145
1998	1.57127
1999	1.3328
2000	0.99552
2001	0.53482
2002	-0.63169
2003	-0.87608
2004	-0.98251
2005	-0.97309
2006	-0.9478
2007	-0.94515
2008	-0.96206
2009	-0.97937
2010	-1.04138
2011	-0.94661
2012	0.40563
2013	0.38383
2014	0.37835
2015	0.35691
2016	0.41545
2017	0.49707