Year Percent 1950 14.76064 1955 15.17727 1960 14.9944 1965 14.58464 1970 14.52728 1975 14.80988 1980 15.36913 1985 15.68026 1990 15.60315 1995 15.96352 2000 17.1777 2005 18.8516 2010 20.88068 2015 22.97815 2020 24.2876 2025 25.30593 2030 25.58158 2035 25.54611 2040 25.37928 2045 25.28197 2050 25.48149 2055 25.97855 2060 26.28994 2065 26.21187 2070 26.01719 2075 25.56839 2080 25.29057 2085 25.10934 2090 24.93746 2095 24.70683 2100 24.42964