Year Percent 1960 4.00531 1961 3.62577 1962 3.78502 1963 3.92207 1964 3.24353 1965 4.16727 1966 3.26252 1967 3.39839 1968 3.51736 1969 3.39784 1970 3.28617 1971 1.70944 1972 2.30377 1973 1.43887 1974 1.01524 1975 0.20182 1976 0.20141 1977 -0.60545 1978 -0.40568 1979 0.80972 1980 1.20242 1981 1.58106 1982 0.97562 1983 1.15831 1984 1.14505 1985 0.94429 1986 0.56233 1987 1.11525 1988 1.2856 1989 0.90827 1990 0.54103 1991 -0.18002 1992 -0.36101 1993 -0.181 1994 0.54201 1995 0.53908 1996 0.17905 1997 0.17873 1998 0.17841 1999 0 2000 0.17809 2001 0.26655 2002 0.45857 2003 0.2752 2004 0.25687 2005 0.04216 2006 -0.28318 2007 -0.38649 2008 -0.40219 2009 -0.00888 2010 1.02802 2011 -0.02636 2012 -0.14072 2013 -0.57727 2014 -0.3334 2015 -0.32204 2016 0.12823 2017 -0.0267