Year	Percent
1960	4.98984
1961	8.02458
1962	8.74794
1963	5.42267
1964	1.91633
1965	-1.0746
1966	2.14164
1967	0.34549
1968	3.0172
1969	0.53396
1970	-3.43569
1971	-4.07756
1972	2.46071
1973	2.52336
1974	-0.54778
1975	-2.39126
1976	-1.18445
1977	4.85728
1978	6.51281
1979	9.16377
1980	7.79538
1981	-1.94685
1982	-0.40163
1983	3.6092
1984	1.76067
1985	8.57256
1986	8.52426
1987	9.60358
1988	6.28567
1989	5.1435
1990	5.3072
1991	4.14528
1992	3.92002
1993	4.52694
1994	2.17942
1995	0.66026
1996	1.4932
1997	1.1294
1998	1.11349
1999	2.52853
2000	2.87999
2001	3.94802
2002	3.79704
2003	2.36829
2004	-0.14384
2005	-0.25579
2006	-1.72948
2007	-1.33539
2008	-1.62051
2009	0.40551
2010	1.24148
2011	0.80925
2012	-1.45194
2013	-2.29908
2014	-1.49721
2015	-1.28806
2016	0.61467
2017	1.36615