I am trying to use Excel to solve for the Future Value of an Investment. The information is above the step 1 instructions. I believe I understand the numbers that I should be inputting into the NPER function in excel, but I keep getting a #NUM! error. Here are the numbers I am inputting into each box:

Rate = 13/12 (I have also computed the number and tried just placing 1.0833333 in the box and that would not work either)

Pmt = -400 (I have also tried using a positive 400 and that did not make it work either

Pv = 10000

FV = left blank (I also tried entering a 0 in the box to see if that would work and it would not.

Usually when I get all information entered the = box underneath all the values boxes shows the answer, but it is not showing anything so I have to be entering some value wrong that it does not like. Can you help? I just also noticed something. When I input the number 100 in the PV box I get a number to populate in the = box (answer) mentioned above. As soon as I add one more zero to make the number larger, the number in the = box (where the answer populates) goes away and then I get the same error message. So, it will work if I don't put a value over 100 in the PV box, but obviously that's not the correct answer.

EXAMPLE 5.12 yFinanceLab Video ER= payments Calculating the Future Value of an Investment In 2015 the average U.S. household owed about $10,000 in credit card debt, and the average APR on credit card debt was about 13.0 percent compounded monthly. On many credit cards the minimum monthly payment is 4 percent of the debt balance. If the average household paid off 4 percent of the initial amount it owed each month, that is, made payments of $400 each month, how many months would it take to repay this credit card debt? Use a financial calculator to solve this problem. STEP 1: Formulate a Solution Strategy The easiest approach here is to either use your financial calculator or use Excel to solve for N, the number of periods. Using Excel, you would simply use the = NPER function and input values for rate, PMT, PV, and FV. Using your financial calculator, you would simply solve for N; however, you'll need to make sure that I/Y is expressed as a monthly rate because you are solving for the number of months neces- sary to repay the credit card