Year annual % 1961 2.1157891175984673 1962 2.1457230593849204 1963 2.190826850939345 1964 2.211359996207875 1965 2.2425674508674547 1966 2.272816410226227 1967 2.2757206267240946 1968 2.2959531838833414 1969 2.3239975478970507 1970 2.368198332125246 1971 2.3975679366381826 1972 2.4353397650056934 1973 2.5117473499820733 1974 2.5970468058790885 1975 2.6835509938001536 1976 2.6970733612559314 1977 2.7357318219659845 1978 2.814037880223296 1979 2.85041023938723 1980 2.845010772048795 1981 2.849793533823771 1982 2.8955002908300713 1983 2.720131076256166 1984 2.6158086443844866 1985 2.7053083762502013 1986 2.7115390367046217 1987 2.713601862379633 1988 2.7310606578470953 1989 2.7669978528621897 1990 2.654931025134033 1991 2.628368797948852 1992 2.730420957459941 1993 2.6713626445976644 1994 2.6306097062977614 1995 2.693235279166899 1996 2.6874994138508868 1997 2.6890289052538634 1998 2.721940716470911 1999 2.7062913067244665 2000 2.749599719173659 2001 2.79965352270915 2002 2.8114526890210954 2003 2.8164806461903567 2004 2.8286422334125945 2005 2.841211220091381 2006 2.8327797447118144 2007 2.8284092989347016 2008 2.8329161508621894 2009 2.8440372024023617 2010 2.8465357411518966 2011 2.848825772217765 2012 2.8128509346212525 2013 2.7618389767510365 2014 2.7507305679848315 2015 2.7233173374171713 2016 2.7130585103698763 2017 2.7062660758635104 2018 2.669238668027347 2019 2.6339820691134435 2020 2.6156461398579154 2021 2.5733774016879494 2022 2.539799442479179 2023 2.5408640904049093