This document contains information about calculating present and future values for annuities using different interest rates and cash flows over time. It includes examples of calculating future value, present value, and future/present value of ordinary and annuities due. It also shows how to solve for the interest rate, payment, or number of periods given the other variables for an annuity. An example problem solves for the interest rate of a 36 month computer lease with monthly payments of $78 and a present value of $1988.13.