Year Percent 1950 7.83328 1955 7.21776 1960 7.0802 1965 6.72577 1970 6.73487 1975 6.86766 1980 6.8898 1985 6.98517 1990 8.24528 1995 9.54619 2000 10.55049 2005 12.31698 2010 15.00317 2015 17.83042 2020 21.12892 2025 24.36423 2030 26.61444 2035 28.4757 2040 30.23524 2045 32.38053 2050 34.13632 2055 36.40384 2060 39.63241 2065 40.95979 2070 40.93163 2075 41.44296 2080 41.88285 2085 42.38017 2090 42.78265 2095 42.8768 2100 42.73861