Year % of total population 1960 75.0928504832704 1961 74.354535239932 1962 73.69636764063462 1963 73.11450699532544 1964 72.51979275923891 1965 72.35923744246865 1966 72.19854363284918 1967 72.013902150623 1968 71.83360803608282 1969 71.66580427664543 1970 71.50347607939746 1971 71.32633613655113 1972 71.12037000470046 1973 70.84202089170898 1974 70.48972503590119 1975 70.11900956012597 1976 69.76283986788496 1977 69.39349378107961 1978 68.83729280376735 1979 68.09362186658363 1980 67.33703264814164 1981 66.55022372875513 1982 65.75796935946788 1983 65.046534477189 1984 64.31596827666453 1985 63.588940778055196 1986 62.869528800297935 1987 62.16021549089103 1988 61.453539936001064 1989 60.75434819436493 1990 60.0551869578865 1991 59.295629613440084 1992 58.51968294327986 1993 57.73449547069468 1994 56.943039374545904 1995 56.14274459620692 1996 55.335091722626196 1997 54.52082843386384 1998 53.692601795773164 1999 52.85187425840449 2000 51.99085883686485 2001 51.06069046233735 2002 50.07050073040355 2003 49.07010021786689 2004 48.05839782669436 2005 47.04459758252904 2006 46.05510461414852 2007 45.08110058257395 2008 44.10071160875588 2009 43.12128435149128 2010 42.14727880679718 2011 41.232940584745954 2012 40.348162902738245 2013 39.467634499421166 2014 38.58999101316142 2015 37.7159542441474 2016 36.8497347105606 2017 35.99531524057407 2018 35.15509169585757 2019 34.33546872575107 2020 33.540664695833335 2021 32.76880075177063 2022 32.02129094636631 2023 31.29232150054559