Year Percent 1950 16.29452 1955 16.38667 1960 16.24948 1965 16.17302 1970 16.19798 1975 16.35895 1980 15.89219 1985 14.86822 1990 15.02416 1995 15.08036 2000 15.92382 2005 16.99434 2010 17.53008 2015 18.23167 2020 19.28715 2025 20.79291 2030 22.37891 2035 22.83518 2040 22.3191 2045 21.68009 2050 21.18669 2055 22.58591 2060 23.8961 2065 24.56817 2070 24.82326 2075 24.227 2080 24.23714 2085 24.58529 2090 24.90186 2095 24.87299 2100 24.54262