Year	Percent
1970	0.13588
1971	0.14876
1972	0.03656
1973	0.14587
1974	0.14905
1975	0.16645
1976	0.26314
1977	0.20704
1978	0.30079
1979	0.36247
1980	0.30714
1981	0.42354
1982	0.35447
1983	1.64824
1984	0.13976
1985	0.6913
1986	0.28351
1987	1.38832
1988	1.35079
1989	0.30599
1990	5.19142
1991	3.43506
1992	0.93914
1993	-2.97312
1994	3.64228
1995	2.79046
1996	-1.7659
1997	-2.3696
1998	0.71396
1999	1.82731
2000	-7.86889
2001	-1.12726
2002	2.11127
2003	0.73129
2004	0.8216
2005	-0.55863
2006	-0.35827
2007	2.90616
2008	0.62971
2009	-1.7081
2010	0.7049
2011	-0.07141
2012	-0.05146
2013	-0.74124
2014	0.70781
2015	-0.00885
2016	-0.47576
2017	0.23607