Year	Percent
1960	-2.89256
1961	-3.64372
1962	-4.47154
1963	-7.69231
1964	-9.16666
1965	-10.15452
1966	-10
1967	-7.43692
1968	-6.31068
1969	-4.88959
1970	-2.16011
1971	-5.21845
1972	-3.34262
1973	-1.79487
1974	-0.82474
1975	-1.59624
1976	-1.65217
1977	-3.16027
1978	-3.0303
2002	-32.90099
2003	-50.7873
2004	-53.14283
2005	-50.07189
2006	-47.61476
2007	-40.52633
2008	-37.07957
2009	-27.49164
2010	-34.91963
2011	-38.08667
2012	-33.62555
2013	-43.44988
2014	-39.20618
2015	-41.7995
2016	-42.12873