Year	Percent
1970	0.05627
1971	0.20226
1972	0.17394
1973	0.13132
1974	0.05607
1975	0.06448
1976	0.13084
1977	0.16704
1978	0.14473
1979	0.11477
1980	0.12274
1981	0.29696
1982	0.19544
1983	0.26155
1984	0.10342
1985	0.06269
1986	0.29762
1987	0.25481
1988	0.21258
1989	0.64733
1990	1.02185
1991	0.74398
1992	0.90222
1993	0.61905
1994	0.60973
1995	0.44954
1996	0.79624
1997	0.93913
1998	1.26823
1999	1.51986
2000	2.79954
2001	1.53133
2002	2.70901
2003	2.62128
2004	2.66859
2005	25.78745
2006	4.78535
2007	20.34067
2008	6.486
2009	3.88774
2010	-3.65526
2011	8.84202
2012	4.50624
2013	2.56466
2014	-0.19786
2015	-0.57996
2016	-7.32538
2017	3.71768
