Commonwealth Consolidated Regulations Commonwealth Consolidated RegulationsFor subsection 58 (3A) of the Act, the factor for determining a parent's adjusted taxable income for a year of income in relation to a child support period is the change in the all employees average weekly total earnings amount for persons in Australia (trend estimate) for the relevant September quarter, from the corresponding quarter of the previous year, as published by the Australian Statistician before the calendar year in which the child support period started.