Obsolescence

Obsolescence is the decline in an asset's usefulness or value that occurs because it has become outdated, not because it has physically worn out. A machine may still run perfectly but be obsolete because newer equipment is far faster or cheaper to operate; a warehouse full of last year's phone models may be in mint condition but worth much less because buyers want the new version. In accounting, obsolescence affects the useful lives used for depreciation, triggers impairment tests for long-term assets and leads to write-downs of inventory.

Obsolescence is one of the two main reasons assets lose value over time. The other is physical deterioration, the wear and tear caused by use, weather and age. Accountants must consider both when estimating how long an asset will be useful to the business.

• Technological obsolescence: newer technology makes existing assets less efficient or uncompetitive. Computer hardware, telecom equipment and software are typical examples, driven by technological progress.
• Functional obsolescence: an asset no longer meets current needs because of its design, for instance an office building without modern cabling or energy systems, or a factory layout unsuited to new processes.
• Economic or external obsolescence: outside factors reduce value, such as a fall in demand, a new competitor, the closure of a key customer or regulation banning a product.
• Inventory obsolescence: stock becomes unsaleable or saleable only at reduced prices because of new models, fashion changes, expiry dates or discontinued product lines.
• Planned obsolescence: a manufacturer deliberately designs products to become outdated, which affects how customers and analysts view expected product lives.

For long-term assets, expected obsolescence should be built into the useful life from the start. Under IAS 16 and US GAAP, useful life reflects expected technical or commercial obsolescence as well as physical wear, which is why laptops are often depreciated over three years even though they may physically last much longer. When obsolescence happens faster than expected, the company shortens the remaining useful life prospectively as a change in accounting estimate. If the asset's value has dropped sharply, it must be tested for impairment and written down.

For inventory, obsolete items are written down to net realizable value, and companies often hold a reserve for obsolete and slow-moving stock based on age and sales history. The charge is usually included in cost of goods sold.

A printing company bought a press for $600,000 three years ago, expecting a ten-year life with no residual value, and has depreciated it at $60,000 a year. Its carrying amount is now $420,000. A competitor launches a digital press that makes the old technology uncompetitive, and the company now expects to use its press for only two more years. The revised depreciation is:

Here $\text{Carrying amount}$ is cost less accumulated depreciation to date, $\text{Residual value}$ is the expected disposal value, and $\text{Remaining useful life}$ is the revised period of use. The new charge is $420,000 divided by 2, or $210,000 a year. If the press's recoverable value is only $250,000, the company first records an impairment loss of $170,000 and then depreciates the remaining $250,000 over two years at $125,000 a year.

Industries with rapid change, such as electronics, fashion and pharmaceuticals, face constant obsolescence risk, and their inventory reserves and useful-life assumptions are key audit areas. Analysts watch for rising inventory alongside slowing sales, which can signal obsolete stock that has not yet been written down, and for companies that extend useful lives to lower depreciation. Obsolescence also matters for lenders using equipment or inventory as collateral, since outdated assets fetch far less in a forced sale. Businesses manage the risk through shorter product cycles, just-in-time manufacturing, leasing rather than buying fast-changing equipment, and careful inventory valuation.