On 1 July 2005 the AER assumed the Australian Competition and Consumer Commission's (ACCC) responsibilities for the regulation of transmission revenues in the National Electricity Market. Under clause 5.6.5A of the National Electricity Code (the predecessor of the National Electricity Rules) the ACCC promulgated the regulatory test in December 1999. The regulatory test is an economic cost-benefit test used by transmission and distribution businesses in the National Electricity Market to assess network investments.
Since 1999, the regulatory test has been reviewed and revised following public consultation.