Year Percent 1950 11.9937 1955 12.93254 1960 14.09298 1965 15.1217 1970 15.93433 1975 16.65701 1980 17.35227 1985 17.88599 1990 21.01408 1995 20.10421 2000 19.38453 2005 19.81217 2010 21.00061 2015 21.80851 2020 23.18446 2025 24.5968 2030 26.31149 2035 27.59665 2040 28.09523 2045 28.64989 2050 29.37387 2055 30.10173 2060 30.72967 2065 31.19621 2070 31.81053 2075 32.29651 2080 32.90695 2085 33.54551 2090 34.16099 2095 34.75252 2100 35.31953