Year	Percent
1991	12.54482
1992	10.17046
1993	6.23685
1994	-1.43862
1995	5.48599
1996	2.44573
1997	1.00523
1998	7.87393
1999	8.45045
2000	8.59469
2001	9.55219
2002	17.46076
2003	15.21663
2004	13.24517
2005	12.20163
2006	9.68681
2007	9.83283
2008	4.47329
2009	6.7807
2010	3.6116
2011	2.24856
2012	1.21457
2013	4.74023
2014	2.30736
2015	0.79687
2016	2.22649
2017	-0.98393