Year	Percent
1964	-0.43923
1965	-2.41527
1966	-3.84042
1967	-4.23595
1968	-3.16498
1969	2.43705
1970	1.74029
1971	-1.11876
1972	-1.26117
1973	1.23513
1974	-2.03661
1975	-9.36277
1976	-7.38644
1977	-7.01026
1978	-4.18522
1979	-7.18077
1980	-15.35266
1981	-16.72342
1982	-10.17763
1983	-10.96423
1984	-1.78055
1985	-1.78694
1986	-3.09331
1987	8.77537
1988	14.33319
1989	6.24686
1990	0.68912
1991	2.2547
1992	-1.31099
1993	-4.29474
1994	3.86303
1995	-7.85238
1996	-14.70506
1997	-1.87863
1998	-7.20956
1999	-6.09338
2000	-21.26028
2001	-19.74451
2002	-21.28695
2003	-18.06332
2004	-12.64668
2005	-11.72671
2006	-8.18203
2007	-9.08822
2008	-12.17509
2009	-14.43699
2010	-17.68762
2011	-48.18356
2012	-27.46346
2013	-30.19929
2014	-21.66572
2015	-28.07752
2016	-29.58782