Year Percent 1950 5.52863 1955 6.13261 1960 6.87655 1965 7.32529 1970 8.24079 1975 8.17796 1980 9.68215 1985 10.11779 1990 12.62007 1995 13.30965 2000 14.4028 2005 15.31423 2010 16.37501 2015 17.46013 2020 19.03721 2025 20.81919 2030 22.70458 2035 24.6138 2040 26.86368 2045 29.07732 2050 31.4054 2055 33.91223 2060 36.39663 2065 38.39429 2070 39.85916 2075 40.40489 2080 40.66675 2085 40.73373 2090 40.73905 2095 40.67706 2100 40.55721