Year % of total population 1960 82.076 1961 81.968 1962 81.782 1963 81.595 1964 81.405 1965 81.215 1966 81.023 1967 80.82900000000001 1968 80.634 1969 80.438 1970 80.24 1971 80.009 1972 79.679 1973 79.34700000000001 1974 79.009 1975 78.668 1976 78.32300000000001 1977 77.974 1978 77.621 1979 77.264 1980 76.902 1981 76.583 1982 76.35300000000001 1983 76.121 1984 75.887 1985 75.652 1986 75.41499999999999 1987 75.17699999999999 1988 74.937 1989 74.695 1990 74.453 1991 74.22200000000001 1992 74.01599999999999 1993 73.809 1994 73.601 1995 73.393 1996 73.18299999999999 1997 72.97200000000001 1998 72.76 1999 72.547 2000 72.333 2001 72.082 2002 71.756 2003 71.428 2004 71.09700000000001 2005 70.765 2006 70.431 2007 70.094 2008 69.754 2009 69.413 2010 69.07 2011 68.724 2012 68.366 2013 67.997 2014 67.616 2015 67.223 2016 66.818 2017 66.4 2018 65.97 2019 65.52799999999999 2020 65.074 2021 64.607 2022 64.128 2023 63.636