Year	Percent
1988	2.11257
1989	3.36751
1990	-6.56001
1991	-8.60169
1992	-9.95838
1993	-14.27369
1994	-22.55085
1995	-11.50332
1996	-9.19776
1997	-2.11217
1998	-1.01931
1999	0.74547
2000	6.97137
2001	10.30354
2002	6.25056
2003	10.29132
2004	12.95366
2005	3.45534
2006	8.0279
2007	8.54588
2008	2.85542
2009	-14.42093
2010	4.61479
2011	5.84534
2012	0.48668
2013	0.20117
2014	-1.14453
2015	-9.44424
2016	2.72093
2017	2.95169