Year Percent 1950 27.15806 1955 27.43139 1960 27.1048 1965 27.32812 1970 27.75695 1975 27.002 1980 26.46805 1985 26.0381 1990 27.46102 1995 26.89038 2000 27.0219 2005 27.23241 2010 28.20152 2015 29.39196 2020 30.22658 2025 30.92476 2030 31.53942 2035 31.5893 2040 31.6636 2045 31.66827 2050 31.36272 2055 31.21259 2060 30.88318 2065 30.44705 2070 29.9593 2075 29.49091 2080 29.03068 2085 28.56233 2090 28.08006 2095 27.56269 2100 27.01889