Year	Percent
1970	0.99087
1971	1.00243
1972	0.87724
1973	0.92133
1974	0.83748
1975	0.66044
1976	0.67363
1977	-0.08742
1978	0.05789
1979	0.00284
1980	0.0232
1981	0.04426
1982	-0.00985
1983	-0.02672
1984	-0.03917
1985	0.05053
1986	0.11974
1987	-0.45254
1988	-0.23076
1989	-0.12286
1990	-0.13896
1991	0.03229
1992	0.22143
1993	0.4259
1994	0.50284
1995	1.65512
1996	0.94585
1997	1.5839
1998	6.94005
1999	0.86031
2000	0.34679
2001	0.05607
2002	0.40838
2003	0.06635
2004	0.14986
2005	1.78621
2006	0.73477
2007	1.30198
2008	1.16856
2009	1.21788
2010	1.20872
2011	2.84582
2012	2.45638
2013	2.41429
2014	2.97526
2015	2.44838
2016	2.06387
2017	1.62178