Year Percent 1950 15.15187 1955 15.80993 1960 15.08844 1965 15.78699 1970 17.0365 1975 18.66588 1980 20.74074 1985 21.13781 1990 21.74754 1995 23.06061 2000 24.21641 2005 25.86154 2010 27.22962 2015 27.36858 2020 27.6461 2025 28.27454 2030 28.87227 2035 29.27533 2040 28.38033 2045 26.71782 2050 24.72643 2055 23.38944 2060 23.25685 2065 23.47779 2070 23.84627 2075 23.64721 2080 23.14445 2085 22.70014 2090 22.56263 2095 22.70303 2100 22.84942