The depreciation expense for the second full year, during which the machine was used 6,400 hours is c.$51,200.
Depreciation expense is an accounting method for recognizing the cost of an asset over its useful life.
Depreciation expense is based on some depreciation methods, including the straight-line, the double-declining balance, the sum of the years' digits, or the units-of-activity methods.
With the units-of-activity method, depreciation expense accounts for the units of activity or usage for the period by multiplying the unit rate by the usage hours or units.
Cost of machine = $180,000
Estimated residual value = $20,000
Depreciable amount = $160,000 ($180,000 - $20,000)
The estimated useful life of 4 years = 20,000 hours
Depreciation expense per hour = $8 ($160,000/20,000)
Depreciation method = Units-of-activity method
Second year depreciation expense = $51,200 (6,400 x $8)
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