Year	Percent
1976	-6.85894
1977	-10.59496
1978	-12.2846
1979	-11.70475
1980	-10.2135
1981	-10.41759
1982	-2.80272
1983	-0.35891
1984	-3.33557
1985	-1.8876
1986	6.63204
1987	2.04738
1988	-4.94037
1989	-7.29639
1990	-7.19828
1991	-3.74355
1992	-3.24233
1993	-6.03904
1994	-8.73789
1995	-2.42431
1996	-0.6867
1997	-4.88122
1998	-0.83165
1999	-3.48086
2000	-0.55865
2001	5.92299
2002	3.03631
2003	1.29055
2004	-2.37191
2005	-6.00329
2006	-10.17499
2007	-9.14146
2008	-13.34827
2009	-9.07539
2010	-10.98173
2011	-12.65065
2012	-11.91579
2013	-13.13491
2014	-11.16711
2015	-10.04701
2016	-9.26225
2017	-12.98905