If your UNDISCOUNTED cash flows add up to more than the cost of the new piece of equipment, what additional information will you NOT need in order to perform a calculation and make a decision if the new piece of equipment will pay for itself in a net-present-value analysis?

Payback period

your hurdle rate

the yearly cash flows

the number of years the piece of equipment will be useful

you will need all four of the other pieces of information to make a decision.