Year % 1964 3.260474651639514 1965 1.9020901442898694 1966 -0.9528714234307684 1967 0.8148270293440661 1968 1.4376882012785452 1969 6.355237351898957 1970 6.9123314629346915 1971 -11.132298616530772 1972 5.617312436154409 1973 -12.667471206820792 1974 -24.37065581307167 1975 14.349193783471923 1976 1.284760433239259 1977 -0.8276474362912227 1978 11.993712387981686 1979 -15.485247977005162 1980 -19.670976535629986 1981 -2.6475942349571335 1982 18.5200896225699 1983 6.11371641015832 1984 14.443483300491545 1985 8.357253912246913 1986 16.099887092650718 1987 -11.501460243049202 1988 30.13116069961512 1989 5.879940258840044 1990 2.1942988898690197 1991 12.78274808417898 1992 -2.0120594497312148 1993 5.279581631182361 1999 -17.678604268188078 2000 -5.566178581093222 2001 -0.17248203827286573 2002 -15.911773635880264 2003 -6.437915462459978 2004 -13.475766084562997 2005 -17.45645574105303 2006 -11.151599276255505 2007 3.475825036549856 2008 -14.315303102778477 2009 41.04610281324958 2010 -11.13238370300516 2011 -14.751767076754145 2012 0.01704960099546749 2013 5.909561344881549 2014 7.0778499384252305