Any account that is offset or deducted from another account is called a “ contra account .” Common contra accounts include allowance for bad debts (an offset to accounts receivable for the amount of accounts receivable that are estimated to be uncollectible), accumulated depreciation (an offset to property, plant, and equipment reflecting the amount of the cost of property, plant, and equipment that has been allocated to current and previous accounting periods), and sales returns and allowances (an offset to revenue reflecting any cash refunds, credits on account, and discounts from sales prices given to customers who purchased defective or unsatisfactory items).