Year Percent 1950 16.16971 1955 15.44885 1960 14.69521 1965 13.76002 1970 12.9659 1975 11.5451 1980 11.85391 1985 10.89795 1990 10.50695 1995 11.69823 2000 11.82015 2005 12.94916 2010 16.46632 2015 18.04625 2020 19.07379 2025 20.21595 2030 21.68279 2035 23.37185 2040 25.22149 2045 26.41486 2050 26.59988 2055 26.42792 2060 26.26624 2065 26.26325 2070 26.56299 2075 26.62011 2080 26.3323 2085 25.90429 2090 25.54312 2095 25.29203 2100 25.08551