Year annual % 1961 0.708741562839802 1962 0.614188134009926 1963 0.536194314138537 1964 0.488998529419177 1965 0.427760811564091 1966 0.689405004046871 1967 0.568473216639124 1968 0.507431317146919 1969 0.432901108958548 1970 0.388015145146731 1971 0.586344189699901 1972 0.568748867126879 1973 0.537331609581752 1974 0.52043158466485 1975 0.489819746380598 1976 0.709469484903307 1977 0.608072630953131 1978 0.535899599260452 1979 0.478502519397543 1980 0.408330497937078 1981 0.582381276293279 1982 0.471540112523836 1983 0.375637683447559 1984 0.280805158775381 1985 0.200093443669341 1986 0.425532557013849 1987 0.291506765323521 1988 0.185062841977923 1989 0.118788372709042 1990 0.0659326192540292 1991 0.126942857726194 1992 0.666421572481417 1993 0.689223724061183 1994 0.45784871504276 1995 -1.4229670890223 1996 -0.0992314596975416 1997 -0.279907993137813 1998 -0.379260986251296 1999 -0.361977304916285 2000 -0.319524801286905 2001 -0.171946646904854 2002 -0.0921469496277098 2003 -0.21273800909834 2004 -0.233328451597809 2005 -0.300431132565912 2006 -0.393204593401 2007 -0.405458541825536 2008 -0.425705551624613 2009 -0.400994905201716 2010 -0.402005900874718 2011 -0.789468997859736 2012 -0.485299545092705 2013 -0.486591387059998 2014 -0.469489291237153 2015 -0.494772574469842 2016 -0.523694463062603 2017 -0.532191341024444 2018 -0.546351968633598 2019 -0.536610017822353 2020 -0.666107601320794 2021 -0.943688169512831 2022 -2.5170575672922 2023 -0.699014137453456