Year	Percent
1981	-0.00268
1982	-5.02658
1983	-2.96189
1984	-6.04298
1985	6.35856
1986	-6.77943
1987	0.64951
1988	-0.44563
1989	-4.04631
1990	-4.68339
1991	-4.1172
1992	30.44553
1993	7.38519
1994	12.70994
1995	13.36016
1996	60.49918
1997	140.50115
1998	18.96109
1999	20.70829
2000	13.52139
2001	56.88336
2002	14.68634
2003	9.32821
2004	32.24777
2005	11.73847
2006	2.96013
2007	10.12357
2008	12.4965
2009	-3.19291
2010	-12.94534
2011	1.89716
2012	3.6926
2013	-8.12737
2014	-3.64609
2015	-12.64424
2016	-12.02638
2017	-6.74722