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ERR from separate inflow and outflow rows

Short answer

Using ε=8%, PW of net outflows = Rs 954,810; FW of net inflows = Rs 773,971. ERR = –4.11%, which is below MARR 10%, so the project is rejected.

Evaluate ERR. MARR = 10%, ε = 8%.

EOY012345
Cash inflow–+40,000+150,00 [?]+120,000+800,000+200,000
Cash outflow-480,000-80,000-50,000500,000-200,000-400,000

Assumptions for unclear entries

  • The year-2 inflow "+150,00" is read as +1,50,000.
  • The year-3 outflow "500,000" has no sign printed; it is placed in the outflow row, so it is taken as −5,00,000.
  • Year-4 inflow is taken as printed, +8,00,000.

Net cash flow (inflow + outflow)

EOYInflowOutflowNet CF
00−4,80,000−4,80,000
140,000−80,000−40,000
21,50,000−50,000+1,00,000
31,20,000−5,00,000−3,80,000
48,00,000−2,00,000+6,00,000
52,00,000−4,00,000−2,00,000
 Net: -4.8L  -0.4L  +1.0L  -3.8L  +6.0L  -2.0L
 yr :   0      1      2      3      4      5

The net flow changes sign four times, so IRR may be multiple; ERR is suitable. ε = 8% is the external reinvestment rate and MARR = 10% is the decision rate.

Step 1: PW of net outflows at ε = 8%

PW = 4,80,000 + 40,000 (P/F, 8%, 1) + 3,80,000 (P/F, 8%, 3) + 2,00,000 (P/F, 8%, 5) = 4,80,000 + 37,037 + 301,656 + 136,117 = Rs 954,810

Step 2: FW of net inflows at ε = 8% (year 5)

FW = 1,00,000 (F/P, 8%, 3) + 6,00,000 (F/P, 8%, 1) = 1,00,000 × 1.2597 + 6,00,000 × 1.08 = 125,971 + 648,000 = Rs 773,971

Step 3: ERR

(1 + ERR)^5 = 773,971 / 954,810 = 0.8106

ERR = (0.8106)^(1/5) − 1 = -4.11%

Answer: ERR ≈ -4.1% < MARR 10%, so the project is rejected (total net outflows exceed total net inflows).

Note: if the year-3 outflow were instead a +5,00,000 inflow, net CF at year 3 would be +6,20,000, giving ERR = 18.0% > 10%, and the project would be accepted.

✓ Answer checked by Claude Opus 5.5 (high effort)

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