Year	Percent
1961	0.40622
1962	3.04524
1963	0.19861
1964	5.07348
1965	5.52953
1966	0.10698
1967	-1.5651
1968	0.32891
1969	6.6347
1970	6.6173
1971	1.44919
1972	-1.16066
1973	0.08889
1974	1.24671
1975	-0.58594
1976	-2.69438
1977	-2.24621
1978	0.03025
1979	2.06508
1980	2.37426
1981	0.4974
1982	2.40037
1983	-4.36395
1984	1.54053
1985	-7.80551
1986	-1.68498
1987	3.9827
1988	-9.72723
1989	-1.55707
1990	1.84542
1991	1.76217
1992	-18.90246
1993	1.94018
1994	-1.40539
1995	-7.81032
1996	1.57488
1997	-6.38219
1998	0.65834
1999	-3.83812
2000	3.69698
2001	-9.80082
2002	20.85619
2003	4.21841
2004	1.89197
2005	0.4662
2006	0.83253
2007	5.06318
2008	2.83477
2009	0.81878
2010	2.92497
2011	3.85528
2012	12.55318
2013	17.99567
2014	2.23671
2015	-22.33077
2016	3.77317
2017	1.93837