# How are compound interest factor tables calculated?

In my economics class, our textbook provides these massive tables for looking up these compound interest factors to put in worth equations. They look something like this:

There has to be some formula for deriving these factors, right? Where are they getting these values from?

• Math? I mean, really, these exponential formulae have been known for centuries (even if not applied to money). The only reason they're still in a book in 2022 is anachronism (or a visual example of the time value of money) because for the past 40 years they'd be calculated by a spreadsheet. Nov 2, 2022 at 16:36
• @RonJohn - don't forget the HP-12c calculator! OK, not nearly as much fun as the HP-15, but still... Nov 2, 2022 at 21:12
• One reason for including tables in textbooks is so you're familiar with them for exams. Exams often have restrictions on the calculators that can be used, and some of the formulae used here would take a fair few steps on a simple scientific calculator such as is often allowed. P×(1+i)^n for interest i and time period n is basic enough but some of the others less so Nov 3, 2022 at 13:15