Year % of total population 1960 38.5153238807462 1961 38.5444445156371 1962 38.5925803449054 1963 38.7460595446585 1964 39.0657084915536 1965 39.3977805073126 1966 39.6773560246352 1967 39.9578918606195 1968 40.2357756905339 1969 40.494928163432 1970 40.7299257726089 1971 40.945190329377 1972 41.145081576635 1973 41.3305360066315 1974 41.5074482904654 1975 41.6723987177658 1976 41.8139921650917 1977 41.9397294302526 1978 42.0549924733476 1979 42.153909416636 1980 42.2410160485135 1981 42.323305279221 1982 42.4021934362762 1983 42.4848282364779 1984 42.5743577518464 1985 42.6663227911208 1986 42.7585087057566 1987 42.8506239637597 1988 42.9374605312416 1989 43.0065204217146 1990 43.0630385066033 1991 43.1249406858277 1992 43.2003833022671 1993 43.2799604440638 1994 43.3639536008797 1995 43.4502256975881 1996 43.5337406830175 1997 43.6105449965976 1998 43.6900094944354 1999 43.7974809981039 2000 43.8819284273114 2001 43.9168692568564 2002 43.9388242961608 2003 43.9419429266851 2004 43.9133024622248 2005 43.8564581986559 2006 43.7844398078135 2007 43.6883157030447 2008 43.5621945372087 2009 43.4087518975118 2010 43.2298517034666 2011 43.0226040243123 2012 42.7852259398586 2013 42.5083079577281 2014 42.1836943442985 2015 41.8143734603931 2016 41.4125237375988 2017 40.9945900168484 2018 40.5736291578942 2019 40.170639898688 2020 39.7851741149668 2021 39.3898279240262 2022 38.9756031977808 2023 38.5400812549795