Year % of total population 1960 83.797 1961 83.292 1962 82.774 1963 82.243 1964 81.701 1965 81.914 1966 82.08500000000001 1967 82.215 1968 82.344 1969 82.47200000000001 1970 82.6 1971 82.708 1972 82.816 1973 82.816 1974 82.708 1975 82.6 1976 82.53999999999999 1977 82.48 1978 82.1 1979 81.383 1980 80.642 1981 79.882 1982 79.098 1983 78.455 1984 77.797 1985 77.126 1986 76.441 1987 75.741 1988 75.026 1989 74.299 1990 73.55799999999999 1991 72.688 1992 71.8 1993 70.89699999999999 1994 69.976 1995 69.039 1996 68.084 1997 67.11699999999999 1998 66.13300000000001 1999 65.13499999999999 2000 64.12299999999999 2001 62.907 2002 61.575 2003 60.224 2004 58.856 2005 57.478 2006 56.132 2007 54.801 2008 53.461 2009 52.12 2010 50.774 2011 49.489 2012 48.235 2013 46.987 2014 45.741 2015 44.5 2016 43.264 2017 42.04 2018 40.848 2019 39.692 2020 38.572 2021 37.488 2022 36.44 2023 35.43000000000001