Year	Percent
1961	4.13191
1962	8.37023
1963	6.71727
1964	7.86297
1965	5.80603
1966	0.25786
1967	3.81194
1968	-1.66125
1969	3.07008
1970	-1.68738
1971	0.18972
1972	-0.87095
1973	3.19027
1974	10.72507
1975	-3.18419
1976	2.02091
1977	5.10151
1978	-10.58432
1979	-28.62661
1980	1.63247
1981	2.43946
1982	-3.49712
1983	1.87288
1984	-4.04959
1985	-6.40509
1986	-3.30687
1987	-2.90619
1988	-14.33633
1989	-3.80197
1990	-2.24569
1991	-2.36358
1992	-1.80419
1993	-2.53569
1994	1.18559
1995	3.8107
1996	4.34101
1997	2.10174
1998	1.94427
1999	5.30524
2000	2.50416
2001	1.46805
2002	-0.62895
2003	1.16814
2004	3.94712
2005	2.93266
2006	2.45483
2007	3.70831
2008	2.09713
2009	-4.52272
2010	3.11552
2011	5.03351
2012	5.2406
2013	3.71579
2014	3.5963
2015	3.59659
2016	3.50336
2017	3.72011