Year Percent 1950 15.47988 1955 14.56814 1960 12.85867 1965 13.17676 1970 12.90099 1975 12.14557 1980 11.88125 1985 12.27433 1990 12.46312 1995 12.2923 2000 12.68707 2005 13.24792 2010 13.43186 2015 15.04352 2020 16.51313 2025 17.30476 2030 17.60998 2035 17.76628 2040 18.3952 2045 19.59521 2050 21.23372 2055 22.43885 2060 22.96477 2065 23.15754 2070 23.16828 2075 23.32767 2080 23.70095 2085 24.07083 2090 24.27536 2095 24.31141 2100 24.25513