The rate of return determined for the incremental cash fl ow series or the actual cash fl ows can
be interpreted as a breakeven rate of return value.
The breakeven rate of return is the incremental i* value, i*, at which the PW (or AW)
value of the incremental cash fl ows is exactly zero. Equivalently, the breakeven ROR is the i
value, i*, at which the PW (or AW) values of two alternatives’ actual cash fl ows are exactly
equal to each other.
Breakeven ROR If the incremental cash fl ow ROR (i *) is greater than the MARR, the larger-investment
alternative is selected. For example, if the PW versus i graph for the incremental cash fl ows in
Table 8–4 (and spreadsheet Figure 8–3 ) is plotted for various interest rates, the graph shown in
Figure 8–4 is obtained. It shows the i * breakeven at 12.65%. The conclusions are that
• For MARR 12.65%, the extra investment for B is justifi ed.
• For MARR
12.65%, the opposite is true—the extra investment in B should not be made,
and vendor A is selected.
• If MARR is exactly 12.65%, the alternatives are equally attractive.
Figure 8–5 , which is a breakeven graph of PW versus i for the cash fl ows (not incremental) of
each alternative in Example 8.3 , provides the same results. Since all net cash fl ows are negative