Year Percent 1961 11.81249 1962 1.03056 1963 4.12021 1964 6.35482 1965 -0.31506 1966 3.21003 1967 1.38061 1968 4.58722 1969 2.03182 1970 2.64221 1971 -0.05558 1972 4.42908 1973 0.22344 1974 2.302 1975 0.02957 1976 4.93531 1977 7.6417 1978 8.51827 1979 2.13763 1980 -2.5338 1981 2.58541 1982 2.13669 1983 -11.73627 1984 -7.13884 1985 -5.36863 1986 -4.35377 1987 -5.45541 1988 -4.68682 1989 -1.54049 1990 0.82089 1991 2.01356 1992 -2.24965 1993 -2.00149 1994 3.07628 1995 4.26663 1996 6.84816 1997 7.32549 1998 7.96493 1999 7.8341 2000 6.63081 2001 3.80863 2002 7.47577 2003 13.8875 2004 7.40731 2005 5.68496 2006 12.66858 2007 4.26485 2008 2.91001 2009 -4.84244 2010 2.81904 2011 -0.79393 2012 0.78056 2013 0.48203 2014 -0.71206 2015 1.09925 2016 -6.29259 2017 -2.63297