The KLN Company is attempting to determine the economically best size of processor machine for their facilities. The six alternative machine sizes which are feasible are as given in Table 9-3. Each machine has a life of 100 years and no salvage value, so that i* = R/I, as in Example 9.3. The company has a total capital budget of $350 000 and a MARR of 15%. Which machine should they buy?
Table 9-3 | |||
Size of
Machine |
Annual Revenue,
R |
Investment,
I |
i* |
Economy | $7 200 | $60000 | 12% |
Regular Super Delux Bulk |
25 000
36 000 45 000 50 000 |
100 000 200 000 220 000 300000 |
25%
18% 20.45% 16.67% |
Extended | 52 000 | 385000 | 20.5% |
The Extended machine is unacceptable according to step 1 of the selection algorithm, and the Economy machine is unacceptable according to step 3. The application of steps 5 and 6 to the four surviving candidates is shown in Table 9-4; step 7 gives Delux as the winner.
Let us examine the logic of the selection algorithm, on the assumption that the company can realize 15% (the MARR) by implementing the do-nothing alternative. Consider the first comparison in Table 9-4. Super costs AI = $100 000 more than Regular, and yields AR = $11 000 more per year. If the company chose Super, it would, in effect, be making $11 000 a year on a $100000 investment; that is, it would be investing at rate Ai* = 11%, whereas it could be earning MARR = 15%. Choosing Super would thus entail an opportunity loss of
(15% – 11%)($100 000) = $4000 per year
Or, looked at in a slightly different way, if the Regular machine is purchased, at a saving of $100 000, the company will earn $25 000 a year on the machine, plus 15% × $100 000 = $15 000 a year on the do-nothing alternative. This is a total annual return of $40 000 on a total investment of $200 000. The same total investment in the Super machine will earn only $36 000 a year.
In this first comparison, it so happens that the economically superior machine has the larger i*-value. Note however, that the eventual winner, Delux, has a smaller i*-value than Regular. As we have seen, when purchase prices differ, a mere comparison of i*-values is not decisive; one must also consider what will be done with any funds left over from the purchase of the cheaper machine.
Table 9-4 | ||
Comparisons | i* | Steps 5 and 6 |
Regular vs. Super |
25% vs. 185 |
\left. \begin{matrix} \text{Standard \#1} \\ \text{vs.} \\ \text{Challenger \#1} \end{matrix} \right\} \to \Delta i^*\ =\ \frac{A\ R}{\Delta\ I}\ =\ \frac{\$36\ 000\ -\ \$25\ 000}{\$200\ 000\ -\ \$100\ 000} = \frac{\$11\ 000}{\$100\ 000} = 11\% < \text{MARR}
Decision: reject challenger #1 and repeat step 5 |
Regular vs. Delux |
25% vs. 20.455 |
\left. \begin{matrix} \text{Standard \#1} \\ \text{vs.} \\ \text{Challenger \#2} \end{matrix} \right\} \to \Delta i^*\ =\ \frac{\$20\ 000}{\$120\ 000}\ =\ 16.7\%\ >\ \text{MARR}
Decision: replace standard #1 (Regular) with challenger #2 (Delux) and repeat step 5 |
Delux
vs. Bulk |
20.45%
vs. 16.67% |
\left. \begin{matrix} \text{Standard \#2} \\ \text{vs.} \\ \text{Challenger \#3} \end{matrix} \right\} \to \Delta i^*\ =\ \frac{\$5\ 000}{\$80\ 000}\ =\ 6.25\% < \text{MARR}
Decision: reject challenger #3 |