Year % of total population 1960 22.758360902196547 1961 23.15874469341641 1962 23.57385761035499 1963 24.00242890087091 1964 24.448888903009784 1965 24.884457788522713 1966 25.34706647787348 1967 25.838389579595 1968 26.360903478311045 1969 26.910120711774272 1970 27.469890659971014 1971 27.89540917230078 1972 28.301083859001302 1973 28.699206541714663 1974 29.07243322856083 1975 29.448906911186835 1976 29.84900127977936 1977 30.258718444569055 1978 30.681996922242117 1979 31.12871583085796 1980 31.602846891693094 1981 31.786825890194034 1982 31.924402442962187 1983 32.061070183541446 1984 32.213255754440766 1985 32.385453883665384 1986 32.577355822790174 1987 32.78852892883003 1988 33.01719467042463 1989 33.2602758681983 1990 33.49115062508039 1991 33.677698905687784 1992 33.82385715093708 1993 33.96329848908646 1994 34.11371092412456 1995 34.285251113360424 1996 34.47486724642769 1997 34.67528755340694 1998 34.894860529455826 1999 35.13443181845378 2000 35.377856227930266 2001 35.488846029420166 2002 35.60443797695011 2003 35.735375446762454 2004 35.880380917256744 2005 36.036686771597 2006 36.207213435455714 2007 36.39491390550077 2008 36.59919642938738 2009 36.79791686185049 2010 36.8967570572708 2011 37.051102675997036 2012 37.206419102128585 2013 37.37596209639479 2014 37.559506303037026 2015 37.75404056486139 2016 37.92346592996879 2017 38.085689952816274 2018 38.23918537426296 2019 38.310999586920104 2020 38.436386792164285 2021 38.61356466030112 2022 38.812635411887726 2023 38.99754836056079