Year % of total population 1960 3.97173723274391 1961 3.98717217665696 1962 3.97535905772278 1963 3.97582080609062 1964 3.99606760934527 1965 4.03470685792832 1966 4.05460963873799 1967 4.03013708186543 1968 3.9796083633475 1969 3.95999520309859 1970 3.96366171592758 1971 3.99031793864271 1972 4.04253712559778 1973 4.09505589328966 1974 4.24335144661713 1975 4.44851740089792 1976 4.60110753534869 1977 4.70346114358847 1978 4.76414984480602 1979 4.75049552792514 1980 4.76347399912804 1981 4.85391564304456 1982 4.93740315234918 1983 5.01447452958495 1984 5.08198117939381 1985 5.1383864688786 1986 5.18497247360173 1987 5.22243453309321 1988 5.25178418150326 1989 5.27420612185478 1990 5.2921240346546 1991 5.1788715764012 1992 4.94982669447637 1993 4.74085436536738 1994 4.54691877971801 1995 4.36721618442888 1996 4.19952753123453 1997 4.03753303926861 1998 3.88097504288172 1999 3.73290265683305 2000 3.59556696231626 2001 3.46812419475417 2002 3.3476124455783 2003 3.23303210153737 2004 3.12585142341291 2005 3.02675376210624 2006 2.93623149562811 2007 2.8555277312923 2008 2.78524742321027 2009 2.72695931856792 2010 2.68054176167297 2011 2.64559044435205 2012 2.62283179067203 2013 2.61236546551986 2014 2.61353552353599 2015 2.62672597250071 2016 2.65154725828084 2017 2.68543400148897 2018 2.72549299217202 2019 2.76887614621282 2020 2.79939558335334 2021 2.81180712964055 2022 2.81955132718502 2023 2.83598237341469