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Depreciation and book value by four methods

Short answer

SL: $1,000/yr, BV $6,000 to $2,000. DB (22.16%): $1,551, $1,208, $940, $732, $569, BV ends $2,000. SOYD: $1,667, $1,333, $1,000, $667, $333. Sinking fund (10%): $819, $901, $991, $1,090, $1,199. All end with BV $2,000.

Considering the following information, compute the annual depreciation and book value of each year by (i) SL method (ii) DB method (iii) SOYD method and (iv) Sinking fund method.

Cost basisSalvage ValueUseful LifeMARR
$ 7,000$ 2,0005 years10%

Data: cost basis P = $7,000; salvage S = $2,000; N = 5; depreciable amount P − S = $5,000; MARR (sinking-fund rate) = 10%.

(i) Straight line

D = (7,000 − 2,000)/5 = $1,000 per year. BV_k = 7,000 − 1,000k.

(ii) Declining balance

The rate that brings the book value to S is R = 1 − (S/P)^(1/N) = 1 − (2,000/7,000)^(1/5) = 1 − 0.7784 = 22.16%. D_k = R × BV_(k−1). Year 1: 0.2216 × 7,000 = 1,551; BV₁ = 5,449.

(iii) Sum of years' digits

Sum = 5(6)/2 = 15. D_k = 5,000 × (6 − k)/15: 1,667; 1,333; 1,000; 667; 333.

(iv) Sinking fund (10%)

Deposit = 5,000(A/F,10%,5) = 5,000(0.16380) = 819. D_k = 819(1.10)^(k−1).

Summary (depreciation D and end-of-year book value BV, in $)

YearSL DSL BVDB DDB BVSOYD DSOYD BVSF DSF BV
11,0006,0001,5515,4491,6675,3338196,181
21,0005,0001,2084,2411,3334,0009015,280
31,0004,0009403,3011,0003,0009914,289
41,0003,0007322,5696672,3331,0903,199
51,0002,0005692,0003332,0001,1992,000

All four methods end with BV = $2,000 at year 5. DB and SOYD are accelerated (large early charges); the sinking-fund method gives small early and large late charges.

✓ Answer checked by Claude Opus 5.5 (high effort)

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