eBook Show Me How Revision of Depreciation. A building with a cost of $480,000 has an estimated residual value of $192,000, has an estimated useful life of 18 years, and is depreciated by the strai a. What is the amount of the annual depreciation? Do not round intermediate calculations. 16,000 b. What is the book value at the end of the tenth year of use? 192,000 X c. If at the start of the eleventh year it is estimated that the remaining life is 10 years and that the residual value is $140,000, what is the depreciation Feedback Check My Wo Asset minus residual value equals depreciable cost Straight-line depreciation allocates the depreciable cost of the asset equally over the period of use. The book value is the fixed asset cost less accumulated depreciation. Revising depreciation is necessary when estimates of residual values and/or useful lives of fixed assets change due to abnormal wear and tear or obsolescence.