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. The ACCC used a post-tax revenue model (PTRM) to set revenue caps for transmission network service providers.

In December 2003 a simplified draft PTRM—Electricity module and corresponding handbook were released. Comments were invited from interested parties.

The AER then updated the PTRM—Electricity module and handbook, which explains the AER's use of the PTRM.