Year % of total population 1960 38.3444535976737 1961 38.668681880109 1962 39.1463895694058 1963 39.788914198937 1964 40.6525024446617 1965 41.9870798685991 1966 43.5225939979303 1967 44.5900619738333 1968 45.0749252470939 1969 45.3177663106658 1970 45.5167657261091 1971 45.640454566918 1972 45.6502570797119 1973 45.5320883355565 1974 45.4364543861354 1975 45.5238740690021 1976 45.6734534727991 1977 45.707434210743 1978 45.7731132831277 1979 45.8902486184399 1980 45.9143107531544 1981 45.8532502667052 1982 45.6986921457119 1983 45.4436975680204 1984 45.220675965898 1985 45.344790908876 1986 45.7691615392611 1987 46.1844450101833 1988 46.4737639704489 1989 46.6476550562777 1990 46.8080566508266 1991 46.9444324790006 1992 46.964168849878 1993 46.8383598642237 1994 46.5287607900048 1995 45.9406757342917 1996 45.078768882075 1997 44.0492120130836 1998 42.868778214437 1999 41.5242475126838 2000 40.0578393771471 2001 38.5466207950272 2002 37.0431447550067 2003 35.5576826349018 2004 34.0796896746317 2005 32.6236572448521 2006 31.0766045219394 2007 29.4558109778978 2008 27.966385955955 2009 26.7036159490255 2010 25.6776957445838 2011 24.8716418229331 2012 24.2682358830519 2013 23.8227675630353 2014 23.3824369267981 2015 22.9426376663866 2016 22.5901893770535 2017 22.2989276990615 2018 22.0526259907955 2019 21.8722993490688 2020 21.7894090249943 2021 21.7181649511226 2022 21.6792322069849 2023 21.6710826712525