1790 3.93 1800 5.31 1810 7.24 1820 9.64 1830 12.87 1840 17.07 1850 23.19 1860 31.44 1870 39.82 1880 50.16 1890 62.95 1900 75.99 1910 91.97 1920 105.71 1930 122.78 1940 131.67 1950 150.70 1960 179.32 1970 203.30 1980 226.55 1990 248.71