Year	Percent
1965	-3.80753
1966	-2.94688
1967	-3.11546
1968	-3.80923
1969	-3.30287
1970	-4.56775
1971	-5.10012
1972	-5.78483
1973	-5.17826
1974	-16.73197
1975	-21.10004
1976	-11.72886
1977	-10.71428
1978	-15.2731
1979	-18.60685
1980	-12.35134
1981	-15.43303
1982	-14.89823
1983	-10.94746
1984	-13.46127
1985	-12.12725
1986	-9.86286
1987	-10.20758
1988	-17.84274
1989	-14.45792
1990	-12.66569
1991	-7.98009
1992	-2.51618
1993	-4.25258
1994	-5.48571
1995	-5.14706
1996	-5.449
1997	-6.05491
1998	-9.49896
1999	-8.25748
2000	-6.6157
2001	-4.85085
2002	-4.35471
2003	-2.58683
2004	-1.35998
2005	-2.26555
2006	-1.61891
2007	-4.57841
2008	-5.59464
2009	-6.6398
2010	-5.23786
2011	-4.12078
2012	-7.91784
2013	-6.33735
2014	-8.43192
2015	-8.47825
2016	-9.33048
2017	-12.18732