Commonwealth Consolidated Acts Commonwealth Consolidated ActsWhere the insurer satisfies the Commissioner that, on account of special circumstances, it is necessary that the rate of tax payable by him under this Division should be ascertained at the time when premiums are paid to him, the Commissioner may direct that the tax so payable in respect of premiums paid during any financial year shall be calculated at the rate which would have been payable if an assessment had been made in respect of those premiums at the date when they were paid.