Year	Percent
1991	-0.79405
1992	-0.18322
1993	-7.13897
1994	-5.62105
1995	0.03249
1996	0.50497
1997	0.9962
1998	-1.51352
1999	-2.68959
2000	-3.63546
2001	-1.2282
2002	-2.00751
2003	-3.92705
2004	-3.91267
2005	-2.25482
2006	-1.08827
2007	0.68786
2008	0.37097
2009	4.03941
2010	5.30618
2011	6.10203
2012	6.68498
2013	6.97507
2014	6.38492
2015	8.85929
2016	10.08102
2017	7.81972