Year Percent 1950 10.09269 1955 10.85636 1960 12.67837 1965 14.2861 1970 15.49917 1975 16.11937 1980 14.73285 1985 15.1418 1990 19.10852 1995 21.1953 2000 22.76598 2005 24.17588 2010 25.46726 2015 28.02542 2020 30.36986 2025 32.66675 2030 34.90063 2035 36.67039 2040 38.70336 2045 40.10692 2050 40.69927 2055 40.25579 2060 39.31726 2065 38.34366 2070 38.15148 2075 38.30122 2080 38.38999 2085 38.38669 2090 38.36893 2095 38.50859 2100 38.89782