Year	Percent
1960	2.40726
1961	4.08247
1962	2.37145
1963	2.41981
1964	2.40701
1965	2.40075
1966	2.14029
1967	2.10756
1968	1.47727
1969	3.17893
1970	2.21461
1971	2.37911
1972	2.47663
1973	1.86797
1974	2.92106
1975	2.58458
1976	1.04029
1977	1.04002
1978	0.98117
1979	0.91864
1980	0.85886
1981	0.86738
1982	0.82265
1983	0.82542
1984	0.77811
1985	0.75356
1986	0.76951
1987	0.65698
1988	0.59022
1989	0.57142
1990	0.50442
1991	0.48347
1992	0.42492
1993	0.4219
1994	0.51418
1995	0.55498
1996	0.4184
1997	0.40066
1998	0.43258
1999	0.3419
2000	0.32761
2001	1.93162
2002	2.28287
2003	2.0934
2004	1.75443
2005	1.57784
2006	1.38058
2007	1.28801
2008	1.12827
2009	0.97695
2010	0.92836
2011	0.09738
2012	-0.073
2013	-0.05873
2014	-0.04723
2015	-0.02183
2016	-0.03215
2017	-0.07923