Year % of total population 1960 15.850505082699698 1961 16.150420439940756 1962 16.407445442118576 1963 16.640152579411534 1964 16.861350721378763 1965 17.081561280579365 1966 17.316774881471467 1967 17.56503435695315 1968 17.83419788394077 1969 18.118723260789775 1970 18.41559886923248 1971 18.729451344827197 1972 18.80847742916252 1973 18.765591152124934 1974 18.727478580086963 1975 18.70023053876679 1976 18.69162820231644 1977 18.69675660143038 1978 18.714903815666535 1979 18.745763435964033 1980 18.79251335585042 1981 18.85544986055723 1982 18.879119506260906 1983 18.88808256633 1984 18.900479522336376 1985 18.912371799014053 1986 18.929508550536692 1987 18.94654442089617 1988 18.95717459841628 1989 18.963480254837943 1990 18.968951276498064 1991 18.977964559717826 1992 18.94996305004163 1993 18.906395767258626 1994 18.870634057779796 1995 18.838540425062472 1996 18.801533886193774 1997 18.760090020153147 1998 18.72327293931981 1999 18.68882169589434 2000 18.649137471341945 2001 18.607662078031947 2002 18.620623734303685 2003 18.610696038049035 2004 18.563410414575614 2005 18.545102109240787 2006 18.562498104919857 2007 18.542166944937318 2008 18.492995981707704 2009 18.482138150766986 2010 18.49894201699106 2011 18.541079759766717 2012 18.565486295475676 2013 18.4254533672606 2014 18.330928846830208 2015 18.422919115117324 2016 18.529179614174414 2017 18.632514364135652 2018 18.744154423836708 2019 19.004338941695757 2020 19.13942279940775 2021 19.280113718910368 2022 19.38553887251407 2023 19.48833503008944