Year Percent 1950 15.00996 1955 15.4923 1960 15.20954 1965 14.83481 1970 14.62247 1975 14.58804 1980 14.81903 1985 14.74085 1990 14.51363 1995 15.16653 2000 16.83675 2005 18.81115 2010 21.09506 2015 22.78167 2020 23.88989 2025 24.80062 2030 25.18951 2035 25.35177 2040 25.57897 2045 25.96222 2050 26.30605 2055 26.88797 2060 27.1682 2065 27.04347 2070 26.91825 2075 26.53889 2080 26.33455 2085 26.21768 2090 26.09055 2095 25.87516 2100 25.58724