A small accounting firm is considering the purchase of a computer software package that would greatly reduce the amount of time needed to prepare tax forms. The software costs $1550 and this expense will be incurred immediately. The firm estimates that it will save $575 at the end of each year beginning in one year for 4 consecutive years, and also save $1581 in year 5. What is the payback on the computer package? Years Place your answer as an integer that stands for number of years