Replenishment of operating stock is always to be expensed as purchased given that the period of consumption, defined as the time between the date of purchase and the date put into service, is expected to be less than one year. These items are considered “movable”, subject to loss and are not to be treated as fixed assets. In locations where it is more economical to purchase operating stock in bulk and infrequently, the expected period of consumption may be greater than one year and, accordingly, it is permissible to record the purchase as inventory and amortize the expense over the period of use to the appropriate department expense (estimated consumption). At no time is the amortization be recorded as depreciation expense. In these instances, on a periodic basis, the property is to verify the accuracy of the estimated consumption by taking a physical inventory of the operating stock that remains unopened and comparing the value to the balance sheet value on the date of the inventory. Variances may result in an adjusting entry, or a correction of the estimated consumption.