Year	Percent
1960	-0.89286
1961	-1.72414
1962	-3.27869
1963	-6.76692
1964	2.01342
1965	-2.18633
1966	-2.21602
1967	-1.08519
1968	-3.07112
1969	-2.43586
1970	-0.93224
1971	-5.73593
1972	-3.34053
1973	-2.31656
1974	-5.78054
1975	-10.72612
1976	-2.92639
1977	0.30419
1978	-8.51871
1979	-8.5595
1980	-14.48268
1981	-12.89435
1982	-16.69547
1983	-15.70218
1984	-12.0483
1985	-9.76028
1986	-10.5924
1987	-15.99373
1988	-13.36241
1989	-13.19782
1990	-19.90215
1991	-18.58781
1992	-20.72777
1993	-17.77907
1994	-18.20999
1995	-14.35194
1996	-9.93308
1997	-4.60443
1998	-11.44053
1999	-8.38823
2000	-9.91578
2001	-10.60564
2002	-12.30222
2003	-14.61348
2004	-17.67062
2005	-25.24181
2006	-39.58769
2007	-26.96537
2008	-28.4344
2009	-36.32116
2010	-30.26241
2011	-28.31178
2012	-28.51872
2013	-26.84953
2014	-25.77064
2015	-23.48796
2016	-25.67441