## Population and percent of change

I was calculating a quadratic fit to update an earlier post I had made about a project idea for Algebra (that integrated quadratic equations with U.S. history). Anyways, while I was using the below data, I was estimating the percent of change of the U.S. population in my head, and then I thought that this would make for an interesting MATH project as well. Students could find the percent of change of every decade, and then they could actually see the figures for certain time periods, such as the Baby Boom of the 1950s (It grew 28,000,000 from 1950 – 1960 as opposed to 14,000,000 from 1960-1970 or 19,000,000 from 1940-1950). I don’t know for sure, but maybe the percent of change would be smaller during the World War or the Civil War? It actually looks like the Civil War didn’t impact the population growth that much. At any rate, wouldn’t it be neat if Math students could relate their percent of change calculations to U.S. Population and historical events that took place during the time period.

Maybe the percent of growth could be seen better with data from every 5 years instead of every 10. I doubt, though, that a census would have been taken more frequently than every decade, and any numbers I may find is probably simply an estimate using some other regression and not truly reflect population variations that may have occurred due to wars, etc. I may make a Math worksheet in regards to this, but it would make a neat Math project for this unit.

1770 2,148,100
1780 2,780,400

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 50,189,209

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 226,542,199
1990 248,709,873