Year Percent 1950 24.08031 1955 20.85331 1960 16.48553 1965 13.69325 1970 11.87481 1975 10.55559 1980 10.49749 1985 10.56113 1990 10.76342 1995 11.25904 2000 11.633 2005 12.0939 2010 12.95767 2015 14.41213 2020 15.95877 2025 16.83381 2030 17.20025 2035 17.06297 2040 17.78293 2045 19.23287 2050 21.30604 2055 22.94718 2060 23.53678 2065 23.66438 2070 23.42496 2075 23.56875 2080 23.90795 2085 24.16007 2090 24.16325 2095 23.93289 2100 23.60351