Year Percent 1950 29.10368 1955 25.40879 1960 24.63542 1965 22.75632 1970 22.26287 1975 21.97548 1980 22.88409 1985 26.76048 1990 28.85526 1995 28.68161 2000 30.83379 2005 32.79492 2010 30.72333 2015 32.38752 2020 34.00862 2025 34.63144 2030 33.97993 2035 32.85825 2040 31.87056 2045 31.1071 2050 30.70289 2055 30.09058 2060 29.14128 2065 28.13255 2070 27.30002 2075 26.6773 2080 26.17215 2085 25.66475 2090 25.11597 2095 24.58474 2100 24.11623