Year Percent 1950 13.34192 1955 14.16023 1960 15.12154 1965 16.20607 1970 17.26453 1975 18.32974 1980 18.84086 1985 19.36439 1990 22.81191 1995 22.07774 2000 22.22848 2005 23.46037 2010 24.86546 2015 25.20635 2020 25.92039 2025 26.94012 2030 28.27568 2035 29.10875 2040 29.31504 2045 29.58437 2050 30.40895 2055 31.59596 2060 31.35745 2065 31.32382 2070 31.78172 2075 32.26544 2080 32.8701 2085 33.4424 2090 33.88184 2095 34.299 2100 34.81361