
Hundreds of books have been written on depreciation, but the book that really
counts is the Internal Revenue Code. Most businesses adopt the useful lives
allowed by the income tax law for their financial statement accounting; they
don’t go to the trouble of keeping a second depreciation schedule for finan-
cial reporting. Why complicate things if you don’t have to? Why keep one
depreciation schedule for income tax and a second for preparing your finan-
cial statements?
Note: The tax law can change at any time, and you can count on the tax law
to be extremely technical. The following discussion is meant only as a basic
introduction and certainly not as tax advice. The annual income tax guides,
such as Taxes For Dummies by Eric Tyson, Margaret Atkins Munro, and David J.
Silverman (Wiley), go into the more technical details of calculating depreciation.
The IRS rules offer two depreciation methods that can be used for particular
classes of assets. Buildings must be depreciated just one way, but for other
fixed assets you can take your pick:
Straight-line depreciation: With this method, you divide the cost evenly
among the years of the asset’s estimated lifetime. Buildings have to be
depreciated this way. Assume that a building purchased by a business
cost $390,000, and its useful life — according to the tax law — is 39 years.
The depreciation expense is $10,000 (1/39 of the cost) for each of the 39
years. You may choose to use the straight-line method for other types of
assets. After you start using this method for a particular asset, you can’t
change your mind and switch to another depreciation method later.
Accelerated depreciation: Actually, this term is a generic catchall for
several different kinds of methods. What they all have in common is that
they’re front-loading methods, meaning that you charge a larger amount
of depreciation expense in the early years and a smaller amount in the
later years. The term accelerated also refers to adopting useful lives that
are shorter than realistic estimates. (Very few automobiles are useless
after five years, for example, but they can be fully depreciated over five
years for income tax purposes.)
One popular accelerated method is the double-declining balance (DDB)
depreciation method. With this method, you calculate the straight-
line depreciation rate, and then you double that percentage. You apply
that doubled percentage to the declining balance over the course of
the asset’s depreciation time line. After a certain number of years, you
switch back to the straight-line method to ensure that you depreciate
the full cost by the end of the predetermined number of years.
The salvage value of fixed assets (the estimated disposal values when the
assets are taken to the junkyard or sold off at the end of their useful lives) is
ignored in the calculation of depreciation for income tax. Put another way, if a
fixed asset is held to the end of its entire depreciation life, then its original
cost will be fully depreciated, and the fixed asset from that time forward will
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Chapter 7: Choosing Accounting Methods: Different Strokes for Different Folks
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