Methods of Depreciation for JAIIB AFM: Formulas & Examples

The methods of depreciation are among the highest-yielding, most predictable topics in the JAIIB Accounting and Financial Management for Bankers (AFM) paper — and once you understand the logic behind them, they become some of the easiest marks on the entire question paper. This guide breaks down every method the exam can throw at you, with clean formulas, fully worked numerical examples, and the practical banking context that helps the concepts actually stick.

Whether you are computing the annual charge on a branch generator, comparing book values across years, or judging whether a borrower has quietly inflated profit by under-charging depreciation, the same core ideas apply. Let us build them from the ground up.

What Depreciation Means in Bank Accounting

Depreciation is the systematic allocation of the cost of a tangible fixed asset over its useful life. It is a non-cash expense: no money leaves the bank when depreciation is charged, yet it reduces both reported profit and the carrying (book) value of the asset on the balance sheet.

Every method shares one purpose — matching the cost of using an asset against the revenue that asset helps generate. This is the matching principle of accounting in action. The cash outflow already happened when the asset was bought; depreciation simply spreads that earlier cost fairly across the years of benefit.

To master AFM from book-keeping fundamentals through to advanced analysis, work through the structured sequence in the JAIIB course, which builds these accounting concepts in the right order.

The Three Drivers of Every Calculation

No matter which of the methods of depreciation you apply, you only ever need three figures:

• Cost of the asset — purchase price plus freight, installation and any cost incurred to bring it into use.
• Useful life — the period over which the asset is expected to remain productive.
• Residual (scrap) value — the estimated amount recoverable when the asset is retired.

Beyond the exam, these methods matter for taxation, asset-replacement planning and honest financial reporting. A banker who reads them well can immediately tell whether a borrower's profit has been flattered by an unrealistically low depreciation charge.

Straight Line Method (SLM): The Foundation

The Straight Line Method is the simplest and most frequently examined of the methods of depreciation. It charges an equal amount every year across the asset's useful life — plotted on a graph, the book value falls in a straight line. SLM suits assets that wear out evenly over time, such as furniture, fixtures and buildings.

SLM Formula

Annual Depreciation = (Cost − Residual Value) ÷ Useful Life

Worked Example — Branch Generator

A bank buys a generator for ₹5,00,000. Installation adds ₹50,000, the expected residual value is ₹50,000, and the useful life is 10 years.

• Depreciable cost = (5,00,000 + 50,000) − 50,000 = ₹5,00,000
• Annual depreciation = 5,00,000 ÷ 10 = ₹50,000 per year

The same ₹50,000 is charged every year until the book value reaches the ₹50,000 residual value at the end of year 10. Expressed as a rate on original cost, that is 1 ÷ 10 = 10% per annum.

SLM's strength is predictability — consistent figures make budgeting easy. Its weakness is that it ignores reality: older assets usually demand higher repairs, so the combined burden of depreciation plus maintenance creeps up over time even though the depreciation charge stays flat. Sharpen your speed on these computations with timed numerical drills on the JAIIB mock tests, where quick, accurate calculation directly converts into AFM marks.

Written Down Value Method (WDV): The Reducing Balance

The Written Down Value Method — also called the diminishing balance or reducing balance method — applies a fixed percentage rate to the book value at the start of each year rather than to the original cost. Because the book value falls every year, the depreciation charge also falls: more is written off early, less later.

This descending pattern mirrors how assets such as computers, laptops and vehicles behave — they are most productive when new and lose value fastest in their early years.

WDV Formula

Depreciation for the year = Rate × Opening Book Value

Worked Example — Office Laptop

A laptop costs ₹1,00,000 and is depreciated at 40% per annum under WDV.

• Year 1: 40% of 1,00,000 = ₹40,000 → closing book value = ₹60,000
• Year 2: 40% of 60,000 = ₹24,000 → closing book value = ₹36,000
• Year 3: 40% of 36,000 = ₹14,400 → closing book value = ₹21,600

Watch how the charge shrinks from ₹40,000 to ₹14,400 in just three years. Under WDV the book value approaches but never quite reaches zero — a realistic reflection of assets that always retain some salvage worth. Lock these definitions into memory with the rapid term-matching activity in the JAIIB matching games.

SLM vs WDV: The Comparison Examiners Love

Exam questions repeatedly ask you to contrast SLM and WDV book values after two or three years, so it pays to see them side by side. Crucially, total depreciation over the full life is the same under both — only the timing differs. WDV front-loads the expense, lowering taxable profit earlier, which many businesses prefer.

A solid grip on this contrast also strengthens your reading of borrower accounts — a skill you will lean on again when you study the AFM subject in depth and analyse financial statements.

Other Methods You Should Recognise

Beyond SLM and WDV, JAIIB AFM expects you to recognise a few specialised approaches, even where the exam calculates them less often.

Units of Production Method

Here depreciation tracks actual usage rather than the passage of time:

Depreciation per unit = (Cost − Residual Value) ÷ Total estimated units

If a machine costing ₹4,00,000 with no scrap value can produce 2,00,000 units, the rate is ₹2 per unit. Produce 30,000 units in a year and the charge is ₹60,000. This method suits machinery whose wear depends directly on output.

Sum of Years' Digits Method

An accelerated method where each year's fraction has the remaining life as the numerator and the sum of the years' digits as the denominator. For a 5-year asset the denominator is 5+4+3+2+1 = 15, so year 1 charges 5/15 of the depreciable cost, year 2 charges 4/15, and so on. Like WDV, it loads more expense into the early years.

How to Choose the Right Method — and a Study Plan

Selecting a method is rarely arbitrary. Use these guiding factors:

1. Nature of the asset: evenly-used assets (buildings, furniture) suit SLM; high-tech, fast-obsolescing assets (computers, vehicles) suit WDV.
2. Consistency: once chosen, a method should be applied consistently year after year, as required by accounting standards.
3. Tax and profit impact: accelerated methods (WDV, Sum of Years' Digits) reduce early profits and defer tax.

Banks and companies must also respect the depreciation rates prescribed under the Companies Act and the Income Tax Act — the chosen method cannot conflict with statutory rates. As per the latest released regulatory framework, always confirm the applicable rates from the official notification rather than relying on memory.

For a focused two-week revision push, try this rhythm:

• Days 1-3: Memorise the SLM and WDV formulas; solve five problems each from scratch.
• Days 4-6: Build SLM-vs-WDV book-value tables for the same asset to internalise the timing difference.
• Days 7-9: Add Units of Production and Sum of Years' Digits; one example each.
• Days 10-14: Attempt full, timed mock sets and review every error.

Pair this with related AFM topics — for instance, depreciation feeds directly into the Cash Flow Statement for Bankers (it is added back as a non-cash item) and into Ratio Analysis for JAIIB AFM, where book values shape return and turnover ratios.

Common Mistakes to Avoid

• Applying the WDV rate to original cost: WDV always uses the opening book value, never the original cost after year one.
• Forgetting installation and freight: these are part of cost and must be included before depreciating.
• Subtracting residual value under WDV: in WDV the rate is applied to book value directly; do not deduct scrap first as you would in SLM.
• Assuming WDV gives more total depreciation: over the full life both methods total the same — only the timing differs.
• Changing methods casually: a switch is allowed only for a truer presentation or by law, and it must be disclosed with its effect quantified.

Keep your fundamentals current by browsing more study guides on the JAIIB guides hub, and for authoritative rules consult the Indian Institute of Banking & Finance.

Frequently Asked Questions

What is the difference between SLM and WDV methods of depreciation?

SLM charges an equal amount every year on the original cost, giving a flat expense, while WDV applies a fixed rate to the reducing book value, so the charge is higher in early years and lower later. The total depreciation over the asset's life is the same under both. WDV's appeal is that it front-loads the expense, lowering taxable profit sooner.

Why is depreciation called a non-cash expense?

Depreciation reduces reported profit and an asset's book value, but no cash actually leaves the business when it is charged. The cash outflow already occurred when the asset was purchased. Depreciation simply spreads that earlier cost across the years the asset is used, in line with the accounting matching principle.

How important is depreciation for the JAIIB AFM exam?

It is a recurring, high-yield topic in Accounting and Financial Management for Bankers. Expect numerical problems on SLM and WDV, book-value comparisons, and conceptual questions on method selection. Practising worked examples under timed conditions is the most reliable way to secure these marks.

Can a company change its depreciation method?

Yes, but only when the change produces a more accurate presentation of the financial statements or is required by law or accounting standards. The change must be disclosed and its financial effect quantified. Frequent or arbitrary changes violate the consistency principle and distort comparability between periods.

Which assets suit the Units of Production method?

The Units of Production method suits assets whose wear depends on output rather than time, such as factory machinery. Depreciation per unit equals (cost minus residual value) divided by total estimated units, and the yearly charge rises or falls with actual production. It links the expense directly to how hard the asset is worked.

How do I calculate the SLM depreciation rate as a percentage?

Divide one by the useful life and express it as a percentage of the original cost. For an asset with a 10-year life, the rate is 1 ÷ 10 = 10% per annum. This flat percentage is then applied to the depreciable cost (cost minus residual value) to give the equal annual charge.

Conclusion: Lock In Your Depreciation Marks

The methods of depreciation reward steady, deliberate practice. Nail down the three inputs — cost, useful life and residual value — master the SLM and WDV formulas, and learn when each method fits. Do that, and these become some of the most dependable marks in the entire AFM paper. Put it to the test with exam-style problems on the JAIIB mock tests, and structure your wider preparation through the JAIIB course to carry this momentum into the rest of the syllabus.

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