Year Percent 1961 2.14927 1962 2.00397 1963 -1.26075 1964 8.38337 1965 2.25078 1966 12.34545 1967 11.09667 1968 0.17875 1969 1.52094 1970 4.37934 1971 4.19528 1972 2.56407 1973 2.23821 1974 1.63283 1975 4.55127 1976 8.529 1977 5.50082 1978 1.07423 1979 1.76824 1980 6.22614 1981 1.67424 1982 -5.96696 1983 1.13165 1984 -0.39656 1985 -2.82159 1986 5.76697 1987 2.91245 1988 3.16809 1989 -0.39943 1990 -0.79846 1991 -3.03588 1992 0.66685 1993 2.45777 1994 -0.0957 1995 3.65476 1996 1.94695 1997 3.96372 1998 3.13963 1999 2.80572 2000 8.34832 2001 6.07137 2002 -2.11673 2003 2.73627 2004 1.65507 2005 1.01808 2006 4.94027 2007 2.26737 2008 0.92905 2009 -5.808 2010 -1.32438 2011 -2.5011 2012 -5.1782 2013 -2.81561