It is unlawful for a company to pay dividends except out of profits. The notional taxable income determined under s. 136 would be an amount, a part or even the whole of which, would not be profits of the company. It would therefore be in part or whole income which the company could not lawfully distribute by way of dividend. In the absence of a clear intention to the contrary, it might have been thought that Part IIIA. of the Act was intended to deal with income which could lawfully be distributed by way of dividend and therefore with the actual taxable income as defined in s. 6 and assessed under s. 166 of the Act. But s. 160C. enumerates deductions which may be made in order to ascertain that portion of the taxable income of a company which has not been distributed as dividends. One of these deductions is the net loss, except to the extent to which it is a loss of a capital nature, incurred by the company in the year of income in carrying on its business out of Australia, provided that this deduction shall not be made in the case of a company the taxable income of which is assessed under Div. 13 (that is under s. 136). It is therefore clear that when the notional taxable income determined under s. 136 is substituted for the actual taxable income, Part IIIA. is concerned with that notional taxable income, and the company becomes liable to pay further tax on that portion of that income which, less all allowable deductions, is not distributed as dividends. There is no specific section of the Act which entitles a taxpayer, who is first assessed under an ordinary assessment and pays tax and is then re-assessed under s. 136, to set off the amount he has paid on the first assessment against his liability under the second assessment. But it seems to me that, when the Commissioner determines the amount of the notional taxable income under s. 136, this amount must be substituted for the actual taxable income. The assessment of the taxpayer on his notional taxable income under s. 169, as the Board said, replaces the assessment of the taxpayer on his actual taxable income under s. 166, and the moneys paid under the earlier assessment must be refunded or set off against his liability under the new assessment. Further the taxpayer, if a company, may, as in the present case, have been assessed and paid further tax under Part IIIA. of the Act on that portion of its actual taxable income which has not been distributed as dividends. The determination by the Commissioner of a notional taxable income for the Company under s. 136 in lieu of its actual taxable income would then necessitate an assessment of the Company for further tax under Part IIIA. upon that portion of the notional taxable income which has not been distributed as dividends. The new assessment would again replace the previous assessment. It would not be an amendment of that assessment. It would be an original assessment.