Year Percent 1961 1.74821 1962 1.43186 1963 4.78095 1964 8.47987 1965 3.83881 1966 2.89558 1967 2.68847 1968 6.14643 1969 0.28169 1970 3.21431 1971 0.50028 1972 4.79645 1973 4.46708 1974 2.54094 1975 2.64505 1976 1.49726 1977 0.62354 1978 6.16271 1979 6.99224 1980 6.63288 1981 6.27312 1982 -2.83199 1983 -6.25451 1984 1.4444 1985 0.4979 1986 -5.67242 1987 -0.12932 1988 -0.70446 1989 2.18901 1990 3.02501 1991 2.17107 1992 1.57915 1993 2.02599 1994 2.95395 1995 -7.98159 1996 4.94117 1997 5.09581 1998 3.52539 1999 1.23826 2000 3.4784 2001 -1.7064 2002 -1.27411 2003 0.21255 2004 2.60441 2005 0.91508 2006 2.9573 2007 0.69632 2008 -0.48083 2009 -6.79735 2010 3.49303 2011 2.12136 2012 2.15128 2013 -0.05838 2014 1.44972 2015 1.90108 2016 1.58236 2017 0.75456