Year	Percent
1978	0.46092
1979	1.3749
1980	2.34684
1981	1.54717
1982	1.63606
1983	2.67392
1984	1.59322
1985	0.58725
1986	1.21344
1987	1.89093
1988	0.41108
1989	-0.29818
1990	0.80577
1991	1.20203
1992	0.09338
1993	14.90666
1994	0.16899
1995	5.90826
1996	2.85666
1997	3.40857
1998	1.68133
1999	22.86462
2000	-3.04039
2001	-4.84426
2002	6.59457
2003	6.28015
2004	1.90162
2005	13.15912
2006	19.24257
2007	16.9437
2008	16.35988
2009	12.34461
2010	12.66456
2011	2.06777
2012	-0.50632
2013	13.33484
2014	20.36515
2015	50.01802
2016	0.64562
2017	13.28529