Year % of total population 1960 10.369939784442618 1961 10.527306084648476 1962 10.681400829318164 1963 10.837264281141316 1964 10.999910040919659 1965 11.173140184919202 1966 11.353846587367427 1967 11.530515297064307 1968 11.712462062344676 1969 11.899439665911205 1970 12.094065353592923 1971 12.293130954365251 1972 12.495955046650684 1973 12.688623036368933 1974 12.884798480697155 1975 12.937726648456144 1976 13.111366838778551 1977 13.282816118288387 1978 13.45477846934833 1979 13.62878225299518 1980 13.808741194326647 1981 13.935416757415432 1982 14.022089444748095 1983 14.120633956962457 1984 14.230014224470905 1985 14.34675002486631 1986 14.471283660376795 1987 14.593534169546375 1988 14.723426394878336 1989 14.861902630768398 1990 15.002185731438605 1991 15.112816211890141 1992 15.215861665939743 1993 15.323525684947814 1994 15.448072135333303 1995 15.575364351193938 1996 15.68452933023859 1997 15.791084646940465 1998 15.905492726375524 1999 16.025556382488986 2000 16.149462538265933 2001 16.25441113491087 2002 16.341264081981194 2003 16.435428898443863 2004 16.534387747270618 2005 16.646623193305068 2006 16.768782180259194 2007 16.898504333649484 2008 17.041075911677307 2009 17.18885893892822 2010 17.314402382721145 2011 17.415284517985 2012 17.535055682808736 2013 17.66607334935036 2014 17.810780374414346 2015 17.98656153633592 2016 18.173309202968525 2017 18.354197680448042 2018 18.544321065650507 2019 18.71121296922566 2020 18.89296483065905 2021 19.094710862035626 2022 19.302504577839386 2023 19.49513201666583