Year	Percent
1960	-1.27057
1961	0.22538
1962	-1.96265
1963	-3.24083
1964	-1.42038
1965	-1.20605
1966	-0.33149
1967	-2.0498
1968	-3.74274
1969	-3.99891
1970	-4.3616
1971	-2.82399
1972	-0.99471
1973	-1.44349
1974	-2.3664
1975	-4.61194
1976	-2.46984
1977	-5.41933
1978	-4.22757
1979	-6.72571
1980	-6.25617
1981	-6.2739
1982	-1.71252
1983	-7.16208
1984	-4.2665
1985	-2.72797
1986	2.03274
1987	0.56004
1988	-1.38953
1989	-2.56388
1990	-7.51851
1991	-6.54252
1992	-4.00969
1993	-4.11152
1994	-4.76473
1995	-6.69149
1996	-6.23731
1997	1.42233
1998	15.63411
1999	12.17081
2000	8.38254
2001	6.2334
2002	6.32176
2003	6.35228
2004	4.53185
2005	-1.04843
2006	3.26373
2007	7.87132
2008	2.39582
2009	9.60782
2010	5.72182
2011	2.03441
2012	1.05174
2013	2.82876
2014	6.77793
2015	11.52591
2016	14.56289