<prompt> Unda chati inayoonyesha ongezeko la watu nchini Marekani kwa miaka mingi.  <response>: Mwaka Idadi ya Watu wa Marekani --- --- 1790 3,929,214 1800 5,308,483 1810 7,239,881 1820 9,638,453 1830 12,866,020 1840 17,069,453 1850 23,191,876 1860 31,443,321 1870 38,558,371 1880 50,155,783 1890 62,979,766 1900 76,212,168 1910 92,228,496 1920 106,021,537 1930 123,202,624 1940 132,164,569 1950 151,325,798 1960 179,323,175 1970 203,302,031 1980 226,545,805 1990 248,709,873 2000 281,421,906 2010 308,745,538 2020 331,449,281 