The payback period is the number of years it takes to recover the initial cost of the investment.
Advantages:
Drawbacks:
Discounted payback method uses the present value of the estimated cash flows; it gives the number of years to recover the initial investment in present value terms.
Drawbacks of discounted payback method:
Example 3
Compute the payback period and the discounted payback period assuming a rate of 10%.
Year | 0 | 1 | 2 | 3 | 4 |
Cash flows | -800 | 340 | 340 | 340 | 340 |
Solution:
Year | 0 | 1 | 2 | 3 | 4 |
Cash flows | -800 | 340 | 340 | 340 | 340 |
Cumulative Cash flows | -800 | -460 | -120 | 220 | 560 |
Discounted Cash flows | -800 | 309.1 | 280.99 | 255.45 | 232.22 |
Cumulative Discounted Cash flows | -800 | -490.9 | -209.91 | 45.54 | 277.76 |
Payback period = Last year with negative cumulative cash flow + unrecovered cost at the beginning of the next year/ cash flow in the next year
Payback period = = 2.35 years
Discounted payback period = = 2.82 years
The discounted payback period is always going to be greater than the payback period, as long as the interest rate is positive. If the interest rate is 0%, both payback periods will be the same.
The average accounting rate of return (AAR) can be defined as:
Average accounting rate of return =
Profitability Index is the present value of a project’s future cash flows divided by the initial investment.
Profitability Index PI =
Profitability Index PI =
Investment decision rule for PI:
Invest if PI > 1.
Do not invest if PI < 1.
Difference between PI and NPV
Consider two projects A and B. Project A has an initial investment of $1 million and an NPV of 0.1 million. Project B has an initial investment of $1 billion and an NPV of 0.2 million. If projects A and B are mutually exclusive, then project B would be chosen because of higher NPV. But, if you consider the profitability index, it gives a different picture.
PI of project A = 1 + 0.1/1 = 1.1
PI of project B = 1 + 0.2 /1000 = 1.0002
Based on PI, project A is more profitable than project B.
NPV profile is a graph that plots a project’s NPV for different discount rates. The NPV is shown on the y-axis with the discount rates on the x-axis. Given the data below, create the NPV profile for project X.
Year | 0 | 1 | 2 | 3 | 4 |
Project | -400 | 160 | 160 | 160 | 160 |
Discount rate | NPV (in $ million) |
0 | 240 |
5 | 167 |
10 | 107 |
22 | 0 |
Two important points on the graph:
Example 4
Draw the NPV profiles for projects X and Y. Discuss the significance of crossover point.
Year | 0 | 1 | 2 | 3 | 4 |
Project X | -400 | 160 | 160 | 160 | 160 |
Project Y | -400 | 0 | 0 | 0 | 800 |
The NPV profile for projects X and Y at different discount rates is tabulated below. Based on these values, the NPV profiles are depicted graphically.
Note: The values are computed for each discount rate using the calculator.
Discount Rate (in %) | NPV for Project X | NPV for Project Y |
0 | 240 | 400 |
5 | 167.35 | 258.16 |
10 | 107.17 | 146.41 |
15 | 56.79 | 57.40 |
18.92 | 22.82 | 0 |
20 | 14.19 | -14.19 |
21.86 | 0 | -37.22 |
Let us plot the NPV profile for both the projects now.
The point at which the NPV for both projects intersect is called the crossover point.
If X and Y are mutually exclusive, the discount rate is used to decide which project is better. At lower discount rates, i.e., to the left of the crossover point, Project Y is better. At higher discount rates, i.e., to the right of the crossover point, Project X is better. For example, at a discount rate of 10%, Project Y is better, whereas at a discount rate of 20%, Project X is better.