Year % of total population 1960 32.9034296758453 1961 34.3533949494214 1962 36.7376294591485 1963 38.7747696467324 1964 40.5144241604688 1965 41.9980621641026 1966 43.2414182755247 1967 44.2621390897722 1968 45.1132950219766 1969 45.8516030213188 1970 46.1479963394043 1971 46.0101481836771 1972 45.8508071998516 1973 45.7155155689204 1974 45.5879034078086 1975 45.4726136858928 1976 45.3609300846977 1977 45.2546539828791 1978 45.1545190133663 1979 45.0395979687952 1980 44.9099886842917 1981 44.7615206211556 1982 44.7387584648995 1983 44.8126878357907 1984 44.7902810607003 1985 44.918720159089 1986 45.1845291901639 1987 45.3561508825374 1988 45.484792119672 1989 45.6087769116476 1990 45.7321987984345 1991 45.7967729355562 1992 45.7699286896727 1993 45.6565664445866 1994 45.4643901244394 1995 45.2031530617612 1996 44.8817502076987 1997 44.4960626489219 1998 44.0236927666241 1999 43.4760380232427 2000 42.8912384709857 2001 42.5689534931423 2002 42.469876502838 2003 42.3399225423789 2004 42.2344749741593 2005 42.1565989714282 2006 42.1159816442349 2007 42.122353093565 2008 42.1571979873968 2009 42.1755703763586 2010 42.1341451697472 2011 42.0402108097794 2012 42.0796158473499 2013 42.2289259226763 2014 42.299883036198 2015 42.26880498798 2016 42.1225856107901 2017 41.8712581686387 2018 41.5374933757287 2019 41.1297349941053 2020 40.6138372949264 2021 40.0376500117656 2022 39.4705767230555 2023 38.9302820075435