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MACRS schedule and after-tax IRR by AW

Short answer

After-tax IRR = 17.6% (exceeds the 15% MARR), and annual worth at 15% = Rs 812 per year (>0). Therefore, the investment is acceptable.

An asset has installed value of 45,000. Sv = 0. It is classed as a 5 year property. Determine approximate MACRS depreciation schedule. Over 6 years it is estimated to generate revenue of Rs. 23,000 per year with annual operating cost 7300. Required rate of return = 15% after tax. Tax rate = 40%. Evaluate after tax IRR with annual worth method.

1. MACRS depreciation schedule (5-year property)

MACRS uses the half-year convention and 200% declining balance (rate 2/5 = 40%), switching to straight line when it gives a larger charge. Salvage value is ignored (S = 0), so the whole 45,000 is depreciated over 6 tax years.

Year 1: 40% × ½ = 20.00%           of 45,000  = 9,000
Year 2: 40% × (100 − 20)% = 32.00%             = 14,400
Year 3: 40% × (100 − 52)% = 19.20%             = 8,640
Year 4: 40% × 28.8% = 11.52% (switch to SL)    = 5,184
Year 5: 11.52% (SL on remaining balance)        = 5,184
Year 6: half-year, 5.76%                       = 2,592

These are the standard MACRS percentages for 5-year property.

2. After-tax cash flow

Revenue = 23,000; operating cost = 7,300; tax rate = 40%; asset value at the end = 0 (no disposal tax). ATCF = (23,000 − 7,300) − 0.40 × (23,000 − 7,300 − depreciation).

YearMACRS %DepreciationTaxable incomeTax (40%)ATCF
120.00%9,0006,7002,68013,020
232.00%14,4001,30052015,180
319.20%8,6407,0602,82412,876
411.52%5,18410,5164,20611,494
511.52%5,18410,5164,20611,494
65.76%2,59213,1085,24310,457
Year   0        1       2       3       4       5       6
CF  −45,000  13,020  15,180  12,876  11,494  11,494  10,457

3. Annual worth and after-tax IRR

AW(i) = [−45,000 + Σ ATCF_k (P/F,i,k)] (A/P,i,6)

iAW (Rs)
15%812
20%-750
At 15%: (A/P,15%,6) = 0.26424
AW(15%) = 3,073 × 0.26424 = 812 > 0
At 20%: AW(20%) = -750 < 0
IRR by interpolation = 15% + 5% × 812/(812 + 750) = 17.6%

(Exact solution of AW(i) = 0 gives 17.6%.)

Answer: After-tax IRR ≈ 17.6%, which is greater than the required 15%, and AW at 15% = Rs 812 per year > 0. The investment is acceptable.

✓ Answer checked by Claude Opus 5.5 (high effort)

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