Year Percent 1950 14.72237 1955 14.23383 1960 13.71635 1965 11.38253 1970 12.57967 1975 13.4968 1980 12.46182 1985 13.61969 1990 17.15576 1995 18.06221 2000 18.65084 2005 19.24854 2010 21.5085 2015 27.66748 2020 30.02307 2025 30.72792 2030 31.27215 2035 30.53781 2040 30.92563 2045 31.62712 2050 32.15512 2055 32.46356 2060 31.32058 2065 29.8833 2070 28.30686 2075 27.13309 2080 26.85283 2085 26.72786 2090 26.46952 2095 26.11173 2100 25.74338