Year Percent 1950 23.70989 1955 24.11293 1960 22.08788 1965 22.21282 1970 22.9483 1975 24.85491 1980 27.11751 1985 25.91897 1990 25.77356 1995 26.68201 2000 26.68769 2005 28.86694 2010 28.39107 2015 27.74439 2020 27.55388 2025 27.5553 2030 27.95045 2035 27.22869 2040 26.51979 2045 25.04754 2050 24.43959 2055 24.449 2060 23.95363 2065 23.98638 2070 23.25842 2075 22.65318 2080 22.44607 2085 22.54222 2090 22.67848 2095 22.6971 2100 22.53225