Year annual % 1961 1.90640928686916 1962 1.85259091659261 1963 1.78529046080254 1964 1.7085753627376 1965 1.62746775192224 1966 1.53994643368749 1967 1.44001514424557 1968 1.34391107993173 1969 1.26269402665095 1970 1.19129738047381 1971 1.13830860965427 1972 1.09915414255334 1973 1.05180709188422 1974 1.0070717817208 1975 0.975054672938791 1976 0.939091145183215 1977 0.894427688649094 1978 0.850876368053154 1979 0.81933371228901 1980 0.820271005932465 1981 0.857067833303503 1982 0.894085297839202 1983 0.896945337134023 1984 0.856054521990204 1985 0.772003706403552 1986 0.683624210503319 1987 0.608246542930588 1988 0.517094199743553 1989 0.400467858883652 1990 0.291458993205271 1991 0.179532623292175 1992 -5.16526304355897 1993 -8.10178118268825 1994 -4.68985898879183 1995 -0.314208288820264 1996 4.10656532533756 1997 3.51986603877969 1998 1.64924947318851 1999 0.91811638851753 2000 0.632139635256837 2001 0.372139796167984 2002 0.0828752170247773 2003 -0.349623550237269 2004 -0.982327609602979 2005 -1.17913407901923 2006 -0.888359591107583 2007 -1.24500087046096 2008 -1.62201585384377 2009 -1.67861781190568 2010 -1.7340375845377 2011 -1.79893469913603 2012 -1.8542587666769 2013 -1.55832890226336 2014 -1.29347782804997 2015 -1.31760658922995 2016 -1.23730578353764 2017 -1.18362667966933 2018 -1.16659481128762 2019 -1.16608133465016 2020 -1.26677102311527 2021 -1.44065259604193 2022 -1.15051398459433 2023 -0.70384174302478