Year % of total population 1960 96.94 1961 96.903 1962 96.866 1963 96.829 1964 96.682 1965 96.161 1966 95.563 1967 94.876 1968 94.088 1969 93.19 1970 92.166 1971 91.002 1972 90.305 1973 89.619 1974 88.89 1975 88.116 1976 87.295 1977 86.428 1978 85.511 1979 84.543 1980 83.521 1981 82.44800000000001 1982 80.511 1983 78.277 1984 75.861 1985 73.276 1986 70.517 1987 67.59899999999999 1988 64.533 1989 61.352 1990 58.067 1991 54.708 1992 53.557 1993 52.714 1994 51.867 1995 51.019 1996 50.17 1997 49.323 1998 48.475 1999 47.628 2000 46.781 2001 45.938 2002 45.43 2003 44.971 2004 44.512 2005 44.056 2006 43.6 2007 42.072 2008 40.556 2009 39.063 2010 37.588 2011 36.135 2012 35.232 2013 34.428 2014 33.632000000000005 2015 32.845 2016 32.06699999999999 2017 31.299999999999997 2018 30.554000000000002 2019 29.828000000000003 2020 29.123000000000005 2021 28.439999999999998 2022 27.775999999999996 2023 27.132999999999996