Year Percent 1950 14.18369 1955 12.74451 1960 15.31146 1965 15.46001 1970 15.79305 1975 15.70988 1980 16.05615 1985 16.04651 1990 15.75589 1995 14.94438 2000 14.15281 2005 13.61881 2010 13.41507 2015 13.77214 2020 13.93373 2025 12.71907 2030 11.67093 2035 10.94013 2040 10.45468 2045 9.97453 2050 9.43651 2055 8.86026 2060 8.28233 2065 7.79537 2070 7.38604 2075 7.05049 2080 6.74538 2085 6.44889 2090 6.19253 2095 5.9701 2100 5.79831