Year Percent 1950 15.60513 1955 15.59598 1960 15.2437 1965 14.81792 1970 14.31018 1975 13.75045 1980 13.18936 1985 12.7703 1990 12.48284 1995 12.39774 2000 12.40055 2005 12.58929 2010 13.30721 2015 14.1759 2020 15.11929 2025 15.63992 2030 15.60211 2035 15.29252 2040 15.2809 2045 15.84362 2050 17.05508 2055 18.39918 2060 19.2692 2065 19.84182 2070 20.25165 2075 20.72788 2080 21.3796 2085 21.96413 2090 22.37939 2095 22.66843 2100 22.93149