Ctrm: Compounding Term

Use Ctrm to compute the number of compounding periods it will take an investment of present value to grow to a future value, earning a fixed interest rate per compounding period. Store the following numbers in the memory registers:

• Register 0: Periodic interest rate

• Register 1: Future value of the investment

• Register 2: Present value of the investment

Ctrm Example:

You have just deposited $8,000 in an account that pays an annual interest rate of 9%, compounded monthly. You want to determine how long it will take to double you investment.

Register 0: 0.01 (interest rate = 9% / 12) Register 1: 16000 (future value) Register 2: 8000 (present value)

Clicking SELECT on Ctrm returns 92.77, which tells you that it would take 92.77 months, or almost eight years, to double your $8,000.