Year	Percent
1960	-0.12244
1961	0.3814
1962	1.14438
1963	1.14556
1964	0.90482
1965	0.44983
1966	0.25944
1967	0.30097
1968	0.38415
1969	0.64214
1970	0.03071
1971	0.6553
1972	0.74048
1973	0.48255
1974	-0.47388
1975	-0.14476
1976	0.18403
1977	0.21231
1978	-0.53823
1979	-0.76089
1980	-0.60162
1981	-0.00203
1982	2.34629
1983	1.1145
1984	0.02077
1985	-4.03925
1986	-2.45712
1987	0.1066
1988	-1.30013
1989	-1.41704
1990	2.95629
1991	3.02603
1992	1.17072
1993	-2.65149
1994	1.30368
1995	1.62794
1996	2.03185
1997	4.45331
1998	4.25995
1999	2.80083
2000	2.37635
2001	2.09693
2002	2.54209
2003	2.15753
2004	2.61715
2005	5.45182
2006	7.59117
2007	8.67174
2008	7.58627
2009	4.30787
2010	3.64553
2011	2.38881
2012	2.70853
2013	2.44473
2014	2.11356
2015	3.24308
2016	2.28294
2017	1.71136