The original value of the appraised value is the purchase price of a new piece of equipment, or the repurchase price of equipment assets in the same condition. The net book value before valuation is calculated by subtracting the depreciation amount that has been taken from the original book value. Note that the assessed value is not the same as the tax amount. In the absence of an invoice, the depreciation or amortization of the assets that are reassessed cannot be deducted before income tax, and must be adjusted when the corporate income tax is settled.