Accelerated depreciation

Accelerated depreciation refers to any one of several methods by which a company, for 'financial accounting' or tax purposes, depreciates a fixed asset in such a way that the amount of depreciation taken each year is higher during the earlier years of an asset’s life. For financial accounting purposes, accelerated depreciation is expected to be much more productive during its early years, so that depreciation expense will more accurately represent how much of an asset’s usefulness is being used up each year. For tax purposes, accelerated depreciation provides a way of deferring corporate income taxes by reducing taxable income in current years, in exchange for increased taxable income in future years. This is a valuable tax incentive that encourages businesses to purchase new assets.

For financial reporting purposes, the two most popular methods of accelerated depreciation are the double declining balance method and the sum-of-the-years’ digits method. For tax purposes, the allowable methods of accelerated depreciation depend on the tax law that the taxpayer is subject to. In the United States, the two currently allowable depreciation methods for tax purposes are both accelerated depreciation methods (ACRS and MACRS).

Companies in many countries pay taxes on profits: revenues minus expenses. There are various types of expenses, including salaries paid to workers, cost of inputs, and amortization and depreciation. Profits for tax purposes will, in most countries, differ from accounting profits or earnings.

Under both financial accounting and tax accounting, companies are not allowed to claim the entire cost of a capital asset (any asset which can be used for many years) as an expense immediately. They must amortize the cost of the asset over some period, usually an approximation of the useful life of the asset. The depreciation basis is the cost incurred by the company in acquiring the asset. The useful life of the asset is determined by looking at Section 168(e)(3) of the United States Tax Code, and is known as the class life of the property. An example would be that a railroad track has a useful life of 7 years. This is not the end of the analysis however, because then it becomes necessary to look at the applicable recovery period of the property. The applicable recovery period determines the number of years over which the property should be depreciated. Section 168(e)(1) provides a table for determining the applicable recovery period. Following our 7 year railroad track, the table states that property with a useful life of more than 4 years but less than 10 years will be treated as 5 year property. Finally, it is important to determine the applicable convention for depreciation. Section 168(d)(4) of the U.S. Tax Code gives three different types: half year convention, the mid-month convention, and the midquarter convention. Conventions determine how much of the depreciation deduction the taxpayer may take the first year. This prevents taxpayers from claiming a full year's deduction when the asset has only been in service for part of the year.

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