Year Percent 1950 29.64794 1955 29.17545 1960 28.54826 1965 27.83098 1970 27.07269 1975 27.55577 1980 27.69773 1985 27.50956 1990 27.21775 1995 26.5008 2000 26.36914 2005 26.74663 2010 27.41243 2015 28.18532 2020 28.88949 2025 29.57075 2030 30.24016 2035 30.77082 2040 31.16304 2045 31.35822 2050 31.35015 2055 31.21571 2060 30.94309 2065 30.57484 2070 30.14327 2075 29.66477 2080 29.17009 2085 28.65877 2090 28.1387 2095 27.62157 2100 27.10485