Year annual % 1961 0.548472356417754 1962 0.612895847822874 1963 0.642362670652079 1964 0.666548205291217 1965 0.649729875576735 1966 0.701396116235274 1967 0.747425220117069 1968 0.519254261579197 1969 0.345331646244521 1970 0.349218946276921 1971 0.446245581370136 1972 0.581190352265189 1973 0.554041398958361 1974 0.170205767697282 1975 -0.265319410736808 1976 -0.176672284747108 1977 0.0383904939016918 1978 -0.080961041675265 1979 -0.170463648025429 1980 0.000105968279182431 1981 0.255018231368981 1982 0.0717170180347239 1983 -0.161600981253917 1984 -0.00629490409206624 1985 0.0469509679089439 1986 0.0635489974692431 1987 0.0632842039083754 1988 0.141570850318539 1989 0.450513899730364 1990 0.762001611316115 1991 0.998418103144403 1992 1.10055228652823 1993 0.824627940995206 1994 0.384869546678302 1995 0.153106260702748 1996 0.135019833748789 1997 0.113316608322994 1998 0.109728368100981 1999 0.194563153264961 2000 0.240466652446524 2001 0.382799394483217 2002 0.49198046425522 2003 0.487133894826838 2004 0.620413127334181 2005 0.681267248299787 2006 0.494797775098466 2007 0.324146535285463 2008 0.313041437661508 2009 0.261953189906348 2010 0.240394299500766 2011 0.337080841831645 2012 0.45593747231891 2013 0.589387254692989 2014 0.781541632525841 2015 1.12099250236958 2016 1.08139629872802 2017 0.694621103604983 2018 0.487071924768999 2019 0.444673639004876 2020 0.415176731565556 2021 0.435671684056384 2022 0.956287797076634 2023 0.996275813585943