Year Percent 1950 18.71163 1955 19.61461 1960 18.91433 1965 18.69193 1970 19.32259 1975 19.70534 1980 20.07341 1985 20.66448 1990 21.4292 1995 22.46642 2000 23.81937 2005 25.33868 2010 25.32722 2015 25.10387 2020 26.44752 2025 27.81477 2030 28.2938 2035 28.39868 2040 27.66468 2045 26.53685 2050 25.7774 2055 25.05809 2060 24.43807 2065 23.80238 2070 23.01421 2075 22.46808 2080 22.18697 2085 22.19522 2090 22.22914 2095 22.15714 2100 21.9638