This form is a sample letter in Word format covering the subject matter of the title of the form.
This form is a sample letter in Word format covering the subject matter of the title of the form.
You could also calculate simple interest only with the formula I = Prt, where I is interest, P is principal, r is interest rate as a decimal, and t is time period. You then need to add the interest to the original principal amount to get the total interest plus principal.
Calculating a Variable Interest Rate To calculate an interest rate that varies over time, simply multiply your future value by your interest rate. If you have $10,000 in savings and your current interest rate is 3 percent, for example, then you'll have $10,300 in savings one year from now.
Fortunately, Excel can be used to create an amortization schedule. The amortization schedule template below can be used for a variable number of periods, as well as extra payments and variable interest rates.