Year annual % 1961 2.3362071788650667 1962 2.3742119375889956 1963 2.4095155843133114 1964 2.4721470177815377 1965 2.5225143501230747 1966 2.5340399084879976 1967 2.597076307605178 1968 2.657150997527964 1969 2.6483209319990095 1970 2.652148550053653 1971 2.6403897535751213 1972 2.576831309661415 1973 2.586446320877215 1974 2.6505751418644365 1975 2.6502559596926574 1976 2.634625669439501 1977 2.552856299907603 1978 2.7233093618439455 1979 2.780583235061428 1980 2.2098580568310524 1981 1.9174147230315555 1982 2.3514651583652153 1983 2.6356217186293236 1984 2.676934004350315 1985 2.6755927761332003 1986 2.5935700974792297 1987 2.613043006662579 1988 2.5718912472558486 1989 2.632657693941809 1990 2.55294504860683 1991 2.543251214354285 1992 3.0036964673581252 1993 3.1724564023742516 1994 2.915554178862223 1995 2.881920551095149 1996 2.956383131614544 1997 2.8348594888817615 1998 2.7505491259994557 1999 2.7925192139908575 2000 2.687607275788423 2001 2.7002064959392555 2002 3.015238350215114 2003 3.0735663867653216 2004 2.910155943885613 2005 2.9188562478256017 2006 3.038429912875486 2007 3.0084236970447904 2008 2.9061187532809925 2009 2.894152653681047 2010 2.8771475921054446 2011 2.859480251610094 2012 2.7585389937330405 2013 2.5616786537626837 2014 2.503727467882271 2015 2.5490000836635716 2016 2.6642373064387215 2017 2.7210654179362024 2018 2.7557707608628164 2019 2.835725959896891 2020 2.8205108633137144 2021 2.727872106602746 2022 2.6965205245423647 2023 2.73630087129024