The figure in the company's accounts which is affected by these discounts and rebates is, of course, the figure which represents "sales" in its trading account. The Commissioner does not contend, and plainly could not contend, that discounts and rebates are not to be brought into account for the purpose of arriving at gross profit. He does, however, contend, in substance, that they are not to be brought into account until they have been actually "allowed" by acceptance of the net price from the customer as payment in full for the liquor to which they relate. The company, on the other hand, contends that its true gross profit for an accounting period will not be shown unless all discounts and rebates "allowed" and "allowable" in respect of sales made during the accounting period are brought into account. For income-tax purposes, it says, either (1) its true assessable income consists of its gross profit so ascertained, or (2) if it be strictly correct to arrive at assessable income on the basis of gross prices for liquor sold in the period, then its outgoings incurred in gaining that assessable income include not only discounts and rebates "allowed" in respect of those sales but discounts and rebates "allowable" in respect of those sales. A discount or rebate treated as allowable in the accounts for one period may, of course, be disallowed in the succeeding period and the gross price actually received. This, however, creates no difficulty. The amount treated as allowable in the first period will simply be added to the figure representing sales in the second period. Before considering the question raised by these contentions, it is desirable to examine further the company's practice in dealing with its customers and keeping its accounts, although I think that the really essential facts are those which I have extracted above from Mr. Evans's evidence.