The process for converting present values into future values is called . This process requires knowledge of the values of three of four time-value-of-money variables. Which of the following is not one of these variables?

(A) The interest rate (I) that could be earned by deposited funds
(B) The present value (PV) of the amount deposited
(C) The duration of the deposit (N)
(D) The trend between the present and future values of an investment
(E) All other things being equal, the numerical difference between a present and a future value corresponds to the amount of interest earned during the deposit or investment period.