Year Percent 1950 27.7853 1955 27.74981 1960 24.27511 1965 22.13215 1970 21.11396 1975 21.03735 1980 23.61274 1985 25.40062 1990 26.15987 1995 25.3011 2000 27.16053 2005 28.67767 2010 30.69756 2015 30.79742 2020 29.58917 2025 28.0719 2030 26.74321 2035 26.79424 2040 26.54144 2045 25.33203 2050 24.06059 2055 22.98303 2060 23.02454 2065 23.47669 2070 23.83947 2075 23.81318 2080 23.40209 2085 22.93459 2090 22.68246 2095 22.70497 2100 22.81702