**NPV**
Hitesh Jain, Student (MBA), India, Member

If the time of cost is not given NPV can't be calculated. If the cost incurred is in the beginning of the period it is an investment, if it is later in the period you have to find out the present value of cost.

For example, if the cost is incurred monthly, you have to discount every month's cost and the sum of all discounted costs will be the net present outflow or investment.