Year	Percent
1971	10.55012
1972	2.38254
1973	5.80768
1974	2.59108
1975	10.49091
1976	-5.09139
1977	-2.09423
1978	-1.78664
1979	-0.02584
1980	9.08922
1981	11.33769
1982	-1.67013
1983	-1.73124
1984	2.7807
1985	0.09623
1986	7.80627
1987	9.7539
1988	2.0766
1989	8.54128
1990	16.98708
1991	-1.02601
1992	0.90074
1993	1.09861
1994	0.47081
1995	2.75072
1996	1.62383
1997	0.81985
1998	0.40257
1999	1.01912
2000	0.24173
2001	-0.02451
2002	3.60729
2003	3.26289
2004	2.89896
2005	4.96167
2006	4.60724
2007	2.79147
2008	-0.95858
2009	-0.30836
2010	1.88087
2011	0.37671
2012	2.79689
2013	4.47076
2014	0.07034
2015	-1.42899
2016	-0.44924
2017	0.19853