Year	Percent
1961	4.63502
1962	4.88875
1963	4.67448
1964	7.54197
1965	5.03914
1966	4.47541
1967	-0.77442
1968	16.1724
1969	-3.85269
1970	4.49088
1971	4.93827
1972	4.64424
1973	2.19949
1974	5.381
1975	19.32622
1976	25.99663
1977	11.37246
1978	9.22839
1979	10.92663
1980	18.26538
1981	13.87275
1982	20.91423
1983	11.10288
1984	1.4194
1985	34.14518
1986	-3.42904
1987	-2.30335
1988	2.62406
1989	2.4562
1990	1.83665
1991	-0.38982
1992	2.78265
1993	-3.43302
1994	24.41257
1995	9.89798
1996	-3.54305
1997	0.82338
1998	-0.41415
1999	4.08472
2000	8.5066
2001	0.42594
2002	-2.37188
2003	1.33642
2004	-4.43979
2005	4.18844
2006	3.33405
2007	1.83823
2008	7.07707
2009	3.48251
2010	2.00903
2011	1.96184
2012	2.69369
2013	6.99704
2014	11.06868
2015	6.16227
2016	6.31529
2017	4.51038