Year	Percent
1976	11.77433
1977	5.25576
1978	-3.66111
1979	7.05102
1980	9.51598
1981	7.05448
1982	1.31287
1983	-3.61802
1984	-6.09747
1985	0.74053
1986	-1.69849
1987	3.68558
1988	2.38105
1989	1.75128
1990	3.3359
1991	0.81085
1992	1.80683
1993	1.27804
1994	-0.26247
1995	3.90748
1996	5.77304
1997	-0.9523
1998	-4.25445
1999	8.44338
2000	11.45954
2001	-2.34931
2002	3.77084
2003	4.07241
2004	8.50142
2005	16.52602
2006	11.96243
2007	12.53396
2008	18.53335
2009	-15.18298
2010	12.49018
2011	13.16539
2012	2.23763
2013	-0.86715
2014	-1.0141
2015	-15.4454
2016	-3.19725
2017	6.31009