Year	Percent
1960	1.23713
1961	2.23598
1962	1.77384
1963	1.32845
1964	0.99318
1965	0.71377
1966	0.38123
1967	0.07214
1968	0.01311
1969	0.18337
1970	0.26137
1971	-0.35956
1972	0.13744
1973	0.48932
1974	0.54521
1975	0.38762
1976	0.21899
1977	0.0386
1978	-0.0386
1979	-0.06436
1980	-0.18042
1981	-0.90053
1982	-0.86275
1983	-0.87026
1984	-0.95141
1985	-1.02131
1986	-1.12059
1987	-1.19548
1988	-1.09807
1989	-0.84211
1990	-0.40958
1991	0.04952
1992	0.28956
1993	0.61167
1994	0.69151
1995	0.65911
1996	0.55169
1997	0.52814
1998	0.50495
1999	0.57011
2000	0.65432
2001	0.79692
2002	0.96254
2003	0.97953
2004	0.95059
2005	0.88385
2006	0.78055
2007	0.71125
2008	0.64966
2009	0.65171
2010	0.64749
2011	0.63716
2012	0.73112
2013	0.77442
2014	0.81065
2015	0.82804
2016	0.85679
2017	0.8965