Year	Percent
1970	0.01315
1971	0.02458
1972	0.0094
1973	0.01558
1976	0.00157
1977	-0.00813
1979	0.03245
1980	0.24714
1981	0.00517
2001	0.02762
2002	1.211
2003	1.26101
2004	3.53611
2005	4.31867
2006	3.37225
2007	1.91683
2008	0.39599
2009	0.44933
2010	1.19707
2011	0.29098
2012	0.2767
2013	0.23841
2014	0.20845
2015	0.88026
2016	0.48071
2017	0.25649