Year	Percent
1960	3.49964
1961	3.65799
1962	3.77587
1963	3.70535
1964	3.63246
1965	3.55475
1966	3.47917
1967	3.43029
1968	3.3601
1969	3.25616
1970	3.23342
1971	2.93198
1972	2.11157
1973	2.06349
1974	1.99871
1975	1.9351
1976	1.89445
1977	1.56357
1978	2.02919
1979	1.81185
1980	1.83692
1981	1.70006
1982	1.31246
1983	1.23941
1984	1.16753
1985	1.16036
1986	1.15332
1987	1.08313
1988	1.05774
1989	0.90089
1990	0.9605
1991	-5.1893
1992	-0.44209
1993	4.17742
1994	0.65817
1995	0.85063
1996	-3.38123
1997	2.15784
1998	-1.13182
1999	1.60391
2000	-2.41957
2001	0.71557
2002	0.31269
2003	0.31359
2004	0.28819
2005	0.37735
2006	0.2638
2007	0.21774
2008	0.27331
2009	0.18346
2010	0.04967
2011	-2.85158
2012	0.02639
2013	0.08115
2014	-0.01856
2015	-0.41008
2016	-0.25773
2017	-0.70532