Year Percent 1950 26.96513 1955 26.63142 1960 26.45145 1965 26.80749 1970 26.69088 1975 27.54337 1980 28.02208 1985 27.92303 1990 28.10959 1995 28.32418 2000 29.13446 2005 30.06049 2010 30.81433 2015 31.45557 2020 31.80378 2025 31.79874 2030 31.50338 2035 30.86311 2040 30.11432 2045 29.41315 2050 28.80308 2055 28.27472 2060 27.6235 2065 26.91567 2070 26.21278 2075 25.55437 2080 24.9474 2085 24.38259 2090 23.84953 2095 23.35023 2100 22.89508