Year % of total population 1960 34.14969474352238 1961 34.67878018776699 1962 35.026043398022345 1963 35.229385772823036 1964 35.24831873030781 1965 35.13874111301637 1966 35.05907830790302 1967 35.03108949656757 1968 34.92454516048953 1969 34.69811899935624 1970 34.41504579787388 1971 34.11385904846865 1972 33.79671964319426 1973 33.47153740045748 1974 33.1188845268749 1975 32.729343989350006 1976 32.33709252437864 1977 31.977377919876652 1978 31.63185735661201 1979 31.35600313360737 1980 31.17921763820308 1981 31.048718833914926 1982 30.965161017695426 1983 30.869344069556874 1984 30.806825479339015 1985 30.800643972022723 1986 30.772854408235304 1987 30.715281205075573 1988 30.62736884875404 1989 30.529824603064146 1990 30.421865680784506 1991 30.275068639228692 1992 30.128985185294617 1993 29.975475926777914 1994 29.764344991024704 1995 29.50239315603475 1996 29.177334466141986 1997 28.79455706782922 1998 28.34220452992373 1999 27.833563117930716 2000 27.29917589736991 2001 26.729906763321466 2002 26.142666499433485 2003 25.573825333981954 2004 25.04196912958318 2005 24.557585325715717 2006 24.133717737983094 2007 23.787819704725774 2008 23.540413063528483 2009 23.35794681888776 2010 23.21974365249864 2011 23.112796887385713 2012 23.04079494664373 2013 23.024761369070493 2014 23.06199262965401 2015 23.132338255375696 2016 23.210080523075845 2017 23.297322944201188 2018 23.397629661284906 2019 23.475424811170598 2020 23.52825353651839 2021 23.555538698475434 2022 23.759198240010733 2023 23.68849309765547