This table shows the population of the United States from 1790 to 1880, in millions of people. Let t=0 correspond to the year 1790. Use a calculator to find an exponential model to fit the data.

The first term is 3.9 which corresponds to 1790 and t = 0
The next term is 5.3
The growth rate is 53/39
The next term is 7.2
Which changes the growth rate to 72/53
The next term is 9.6
and the growth rate changes again to 96/72
For us to write this as an exponential function, the growth rate has to be constant.