Year % of total population 1960 36.9994204603152 1961 36.8675573259965 1962 36.8685627426807 1963 36.8123840000423 1964 36.5115241344027 1965 36.1798134603632 1966 35.7959108430338 1967 35.3083343142507 1968 34.6992851765327 1969 34.0100391704568 1970 33.294794792076 1971 32.6259528299836 1972 31.9513652230666 1973 31.2354946708493 1974 30.530086258813 1975 29.8529379435213 1976 29.207608932757 1977 28.6467391497884 1978 28.214339421327 1979 27.8822935966295 1980 27.6232116759997 1981 27.4407742246863 1982 27.282269527449 1983 27.1167890050906 1984 26.9597401696199 1985 26.7999281540102 1986 26.6364983114133 1987 26.46615560203 1988 26.2735597762229 1989 26.0419108121599 1990 25.7549748700453 1991 25.3224355644415 1992 25.0965487252991 1993 25.1711033089905 1994 25.1573992595557 1995 24.9367176017307 1996 24.5109191513196 1997 23.9549683208069 1998 23.3321799075885 1999 22.8110190912691 2000 22.4774287508118 2001 22.2792716803092 2002 21.998298088328 2003 21.583956680914 2004 21.1365860508427 2005 20.6455833979783 2006 20.1442715557413 2007 19.6786110599149 2008 19.2489359978564 2009 18.8324889492353 2010 18.4557423054807 2011 18.1041242916705 2012 17.7917558555031 2013 17.5304815324594 2014 17.3097685783105 2015 17.1166036199894 2016 16.9116044196842 2017 16.676613895454 2018 16.4229939942966 2019 16.2245007038203 2020 16.1207708976224 2021 16.0657861581397 2022 16.0105913335341 2023 15.9203789269586