Year Percent 1950 15.61343 1955 13.94897 1960 13.90794 1965 14.79824 1970 16.68974 1975 15.59731 1980 12.53451 1985 12.50242 1990 13.36872 1995 11.96191 2000 13.1105 2005 12.14413 2010 11.95822 2015 12.1375 2020 11.17118 2025 10.20341 2030 9.96776 2035 10.02625 2040 9.98227 2045 9.66224 2050 9.05833 2055 8.40517 2060 7.99018 2065 7.85862 2070 7.764 2075 7.52225 2080 7.11002 2085 6.66624 2090 6.32561 2095 6.15313 2100 6.05629