You could use various points(x and y coordinates)and implement the proper regression analysis to find an equation. Then revolve.

There are linear regressions, cubic regressions, quartic and quintic regressions, exponential, etc.

A lot of the calculators do these analyses.

For example, suppose we had x values, respectively, of 0,1,2,3,4

y values of 0,2,5,7,11

I ran these through my calculator and got an equation of

Hope this helps a little.