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ERR with MARR 12% and reinvestment 14%

Short answer

Outflows are discounted to present worth at 14% and inflows compounded to future worth at the same rate; the rate equating them is the ERR. ERR ≈ 16.19%, exceeding the MARR of 12%, so the project is acceptable.

Calculate the ERR of the following cash flow. MARR = 12%, reinvestment rate = 14%.

EOY012345
Cash flow-90,00025,00040,000-30,00050,00075,000

The ERR method moves all net outflows to time 0 and all net inflows to the end of the project at the external reinvestment rate ε. ERR is the rate that equates the two. Accept if ERR ≥ MARR. Here ε = 14% and MARR = 12% (used only for the decision).

 EOY :  0        1       2       3       4       5
 CF  : -90,000 +25,000 +40,000 -30,000 +50,000 +75,000

Step 1: PW of outflows at ε = 14% (years 0 and 3)

PW = 90,000 + 30,000 (P/F, 14%, 3) = 90,000 + 30,000 × 0.67497 = Rs 110,249.15

Step 2: FW of inflows at ε = 14% (at year 5)

FW = 25,000 (F/P, 14%, 4) + 40,000 (F/P, 14%, 3) + 50,000 (F/P, 14%, 1) + 75,000

  • 25,000 × 1.68896 = 42,224.00
  • 40,000 × 1.48154 = 59,261.76
  • 50,000 × 1.14 = 57,000.00
  • 75,000
  • Total = Rs 233,485.76

Step 3: ERR

(1 + ERR)^5 = 233,485.76 / 110,249.15 = 2.1178

ERR = (2.1178)^(1/5) − 1 = 16.19%

Answer: ERR ≈ 16.19% > MARR 12%, so the project is acceptable. (The cash flow changes sign three times, so IRR may be unreliable; ERR avoids this problem.)

✓ Answer checked by Claude Opus 5.5 (high effort)

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