Year Percent 1950 3.11848 1955 3.40681 1960 4.3387 1965 5.41926 1970 6.89484 1975 8.44035 1980 9.46244 1985 9.44524 1990 11.71054 1995 11.21893 2000 12.39499 2005 13.31071 2010 16.5282 2015 19.7216 2020 23.59868 2025 27.87225 2030 30.54659 2035 32.13718 2040 32.87283 2045 32.47954 2050 31.27002 2055 31.7328 2060 32.66186 2065 33.50237 2070 34.28834 2075 34.30839 2080 34.45072 2085 34.80337 2090 35.36031 2095 35.88817 2100 36.2462