Year	Percent
1978	3.74443
1979	7.77988
1980	8.28809
1981	4.34915
1982	0.7683
1983	6.55386
1984	11.5887
1985	9.09844
1986	13.07042
1987	8.14141
1988	6.44806
1989	5.93314
1990	2.90508
1991	1.24933
1992	-0.49741
1993	3.00551
1994	4.0271
1995	-6.82784
1996	3.77294
1997	2.60707
1998	1.96125
1999	1.19856
2000	4.45411
2001	-6.60006
2002	-0.39173
2003	4.81014
2004	4.58154
2005	5.22492
2006	11.42022
2007	7.96812
2008	-1.216
2009	-13.14349
2010	-8.25879
2011	-3.16146
2012	2.37504
2013	-1.17312
2014	3.98475
2015	2.96883
2016	4.25737
2017	2.27442