Year Percent 1950 24.47366 1955 25.21394 1960 25.2357 1965 24.89245 1970 23.66108 1975 22.38115 1980 22.0565 1985 23.26483 1990 25.50188 1995 26.87943 2000 27.78308 2005 28.19286 2010 27.56862 2015 27.37134 2020 26.71772 2025 24.84059 2030 23.38754 2035 23.76085 2040 24.22556 2045 24.99926 2050 25.21225 2055 24.00813 2060 23.24331 2065 23.12209 2070 23.06331 2075 23.49221 2080 23.61027 2085 23.32464 2090 22.89544 2095 22.60759 2100 22.53443