Year Percent 1950 26.79107 1955 26.04718 1960 25.63885 1965 25.76849 1970 25.2512 1975 25.42485 1980 25.5219 1985 25.61314 1990 26.1874 1995 26.88135 2000 27.20324 2005 27.73592 2010 27.85512 2015 28.31164 2020 28.95458 2025 29.55375 2030 30.14841 2035 30.60542 2040 30.88443 2045 31.08013 2050 31.15006 2055 31.12128 2060 31.06652 2065 30.94219 2070 30.76241 2075 30.55569 2080 30.33047 2085 30.1181 2090 29.90307 2095 29.68329 2100 29.44922