Year % of total population 1960 14.624216817724152 1961 14.92996295393591 1962 15.24511818416704 1963 15.580253674147436 1964 15.930408165577273 1965 16.292792453343488 1966 16.653910912247515 1967 17.024101217400958 1968 17.40327596436207 1969 17.792961479603182 1970 18.172001508680335 1971 18.583036815669004 1972 19.013252236895035 1973 19.445423004574533 1974 19.867207881235665 1975 20.296389923250878 1976 20.732412488322026 1977 21.16139071379726 1978 21.600878912609765 1979 21.995194430311642 1980 22.38172471909617 1981 22.79876977872181 1982 23.207921164414156 1983 23.655545853447503 1984 24.15248262536174 1985 24.694417481597746 1986 25.262460615183038 1987 25.831558160144926 1988 26.39958534831433 1989 26.960250196667946 1990 27.510868504833194 1991 27.94998217159518 1992 28.379386946066944 1993 28.80978289373831 1994 29.236112767012983 1995 29.62935289181237 1996 29.96578436343929 1997 30.320545915161176 1998 30.685205095288687 1999 31.047552039910684 2000 31.40950851281989 2001 31.8358310239856 2002 32.27265928000124 2003 32.71165939991535 2004 33.15567697793982 2005 33.6156888656079 2006 34.07315999308853 2007 34.48860623725487 2008 34.99170977405093 2009 35.499628613873625 2010 36.01518019856796 2011 36.537014187250016 2012 37.048531690270615 2013 37.56187323420577 2014 38.089067587354435 2015 38.6313191921447 2016 39.160903764527674 2017 39.687196500395395 2018 40.22454532634238 2019 40.75928286371362 2020 41.29441612369847 2021 41.8300528682987 2022 42.36829669370158 2023 42.91023695603694