Year annual % 1961 2.71675130165837 1962 2.74617352457544 1963 2.76502262074288 1964 2.78744682258673 1965 2.48501063159991 1966 2.34794789135738 1967 2.57341447769844 1968 2.6723791375248 1969 2.72107766834073 1970 2.70856557811281 1971 2.67059342228382 1972 2.63262496160996 1973 2.60351109549222 1974 2.56185276046071 1975 2.52215795384658 1976 2.489691100482 1977 2.45293416202066 1978 2.42883466339716 1979 2.4076663007879 1980 2.37932952200941 1981 2.34066633687342 1982 2.30844263861505 1983 2.26871796150833 1984 2.20569643602313 1985 2.10887582043187 1986 1.9966681756408 1987 1.92425957581405 1988 1.88061055652599 1989 1.83542933625866 1990 1.77829086687315 1991 1.74217749925866 1992 1.71013530352426 1993 1.67182800963408 1994 1.65068557714402 1995 1.63416751970142 1996 1.61881686064568 1997 1.60308930027037 1998 1.56493286270644 1999 1.50004294345816 2000 1.44708848408903 2001 1.4100988547982 2002 1.37351928060869 2003 1.33804389134874 2004 1.27322648868512 2005 1.26074829560286 2006 1.29930889873663 2007 1.31184759614566 2008 1.30217053507895 2009 1.27153208994292 2010 1.25151729140412 2011 1.25573808861315 2012 1.25594145835811 2013 1.21281780987831 2014 1.15950664180271 2015 1.1108549322781 2016 1.05894205868913 2017 1.00643952446092 2018 0.966206435866139 2019 0.937689273635294 2020 0.840389268128048 2021 0.694717688319757 2022 0.636555115146439 2023 0.735139895418266