Year Percent 1950 22.97105 1955 20.6255 1960 16.53732 1965 14.99797 1970 15.19302 1975 14.90395 1980 15.22304 1985 13.73201 1990 11.89875 1995 12.57989 2000 14.51017 2005 17.72163 2010 19.95152 2015 21.07933 2020 21.78623 2025 22.99481 2030 25.44219 2035 27.47732 2040 27.91552 2045 26.86289 2050 25.93693 2055 25.5933 2060 26.18718 2065 26.94322 2070 26.51388 2075 25.57178 2080 24.85337 2085 24.69229 2090 24.79607 2095 24.71797 2100 24.32764