Year % of total population 1960 26.388999999999996 1961 25.783 1962 25.233000000000004 1963 24.691000000000003 1964 24.156000000000006 1965 23.631 1966 23.111999999999995 1967 22.602000000000004 1968 22.099000000000004 1969 21.605999999999995 1970 21.120000000000005 1971 20.679000000000002 1972 20.257000000000005 1973 19.842 1974 19.433000000000007 1975 19.031000000000006 1976 18.634 1977 18.245000000000005 1978 17.861000000000004 1979 17.483999999999995 1980 17.113 1981 16.686999999999998 1982 16.241 1983 15.805999999999997 1984 15.379000000000005 1985 14.962000000000003 1986 14.555000000000007 1987 14.156999999999996 1988 13.766999999999996 1989 13.387 1990 13.016000000000005 1991 12.671999999999997 1992 12.457999999999998 1993 12.248000000000005 1994 12.040000000000006 1995 11.835999999999999 1996 11.634 1997 11.436000000000007 1998 11.241 1999 11.048000000000002 2000 10.858000000000004 2001 10.671000000000006 2002 10.489999999999995 2003 10.313999999999993 2004 10.14 2005 9.968999999999994 2006 9.799999999999997 2007 9.634 2008 9.469999999999999 2009 9.308999999999997 2010 9.150999999999996 2011 9.010000000000005 2012 8.879000000000005 2013 8.751000000000005 2014 8.623000000000005 2015 8.497 2016 8.373000000000005 2017 8.251000000000005 2018 8.129999999999995 2019 8.009 2020 7.888999999999996 2021 7.771000000000001 2022 7.653000000000006 2023 7.537000000000006