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If the asset is written off before it is fully depreciated, the last month depreciation expense is recorded as a standard month depreciation amount. If write off is recorded in the last month of useful life of this asset, the current depreciation amount will be calculated as the difference between the depreciable cost and accumulated depreciation and thus will include the "overlooked" depreciation amounts that were not calculated in due months.
The Net Book Value column shows the current value of the fixed asset calculated as the gross cost minus the accumulated depreciation if write off takes place before the end of useful life was reached. On reaching the end of useful life, it is the salvage value.
If in the month of write off the Accumulated Depreciation is greater than the Depreciable Cost, the current depreciation is recorded as zero. For more information, refer to Fixed Asset Write Offs.
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