Year	Percent
1981	3.64865
1982	0.79584
1983	-1.0168
1984	-3.3075
1985	-0.2906
1986	3.61466
1987	-2.7495
1988	-3.26252
1989	6.92362
1990	-11.18791
1991	-29.16327
1992	-6.63552
1993	10.27079
1994	8.96688
1995	14.00202
1996	9.78018
1997	-10.27846
1998	9.69705
1999	14.22232
2000	7.34864
2001	8.95809
2002	4.54441
2003	6.16998
2004	6.15227
2005	6.26328
2006	6.09829
2007	6.70334
2008	4.56012
2009	4.05145
2010	4.22622
2011	2.82641
2012	1.5876
2013	1.18597
2014	1.98531
2015	2.51685
2016	3.51753
2017	3.93691