Year % of total population 1960 40.90117516939043 1961 40.97086385746325 1962 41.13991002149625 1963 41.48148974680595 1964 41.76435740117408 1965 41.891839134067 1966 41.95216172561751 1967 41.91765273821277 1968 41.855755447048644 1969 41.806972079271205 1970 41.71637419931996 1971 41.62353232414396 1972 41.48005291964814 1973 41.32167957395183 1974 41.23014180887267 1975 41.144217816243675 1976 41.03990303489617 1977 40.777655894507696 1978 40.2714490887791 1979 39.75407079584856 1980 39.31884115911552 1981 38.92390852400784 1982 38.60500167843182 1983 38.26206760538822 1984 37.87691233518529 1985 37.51842361789851 1986 37.19316187162779 1987 36.92328270558086 1988 36.66886644189328 1989 36.440235358282706 1990 36.270782547027174 1991 36.088746649084904 1992 35.888236146504724 1993 35.68468996637036 1994 35.42774400980422 1995 35.1162038436336 1996 34.7660135916044 1997 34.36186504086355 1998 33.94252525991042 1999 33.529030264105664 2000 33.10296582130446 2001 32.65705436283226 2002 32.1921589683485 2003 31.737156897761746 2004 31.292453217995586 2005 30.847716615217248 2006 30.45796598745616 2007 30.149102721487647 2008 29.88860514904645 2009 29.660757254861565 2010 29.451109187047333 2011 29.25880740069336 2012 29.09595623119964 2013 28.952755292435253 2014 28.81077893482514 2015 28.653464507746644 2016 28.485030403286274 2017 28.319650363776713 2018 28.13705738003859 2019 27.927371106836098 2020 27.694291137622457 2021 27.449915167471946 2022 27.20806403093798 2023 26.92852531350335