What is the formula for calculating the future value of an annuity?

What is the formula for calculating the future value of an annuity?

The formula for calculating the future value of an annuity is:

FV = P * [(1 + r)^n - 1] / r

Where:
FV = Future Value of the annuity
P = Periodic payment or cash flow
r = Interest rate per period
n = Number of periods

This formula assumes that the periodic payments are made at the end of each period. If the payments are made at the beginning of each period, the formula would be slightly different.