Year	Percent
1978	6.65533
1979	6.2042
1980	-1.02315
1981	-0.22247
1982	1.30671
1983	0.508
1984	0.9866
1985	4.42351
1986	6.94059
1987	9.93503
1988	4.35072
1989	5.04569
1990	4.64565
1991	1.2058
1992	-1.61008
1993	-3.06284
1994	0.56823
1995	1.26358
1996	3.87769
1997	4.67694
1998	11.53673
1999	6.76825
2000	4.70526
2001	-2.24515
2002	3.18304
2003	9.16993
2004	-0.91941
2005	12.95068
2006	-4.28091
2007	5.7879
2008	0.61492
2009	-6.94162
2010	-0.87338
2011	0.38315
2012	-1.53575
2013	1.93867
2014	6.88798
2015	5.97663
2016	3.20651
2017	3.24161