Outturn Inflation

Outturn Inflation

  • Submissions
  • Project Overview
  • Regulatory Process

On 22 March 2018, the QCA clarified its position on DBCTM’s proposal to use the latest ABS inflation index to calculate outturn inflation. Subject to considering feedback from stakeholders, the QCA said it was minded to accept that DBCTM’s proposal was consistent with the 2017 access undertaking (Schedule C, part A, cl. 4(a)) and to permit DBCTM to use the most recent ABS inflation index to calculate outturn inflation in the future.

The QCA did not receive any submission on this matter. Consequently, the most recent ABS inflation index was applied to calculate outturn inflation in the 2018–19 annual revenue requirement (ARR) amendment process.

DBCTM’s proposal and the QCA’s letter to DBCTM can be downloaded below.

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DBCT Management (DBCTM) proposed to change the inflation index used to calculate outturn inflation, which is applied to the regulatory asset base (RAB) when amending the annual revenue requirement (ARR) each year.

The change to directly use the latest inflation index was initially proposed in DBCTM’s modelling draft amending access undertaking (Modelling DAAU) in September 2017. However, the proposal was not in a form the QCA could consider and as such the QCA ceased considering the Modelling DAAU.

DBCTM subsequently proposed the change via a letter. The change was suggested as an improvement over current practice, subject to the QCA’s agreement the update was consistent with the DBCT 2017 Access Undertaking.

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14 September 2017

DBCTM Modelling DAAU proposed changes including inflation index.

27 October 2017

DBCT User Group submission on DAAU.

15 December 2017

QCA ceased considering Modelling DAAU.

30 January 2018

DBCTM letter proposed to update index for outturn inflation.

22 March 2018

QCA clarified its position on the proposal.

20 April 2018

Stakeholder submissions due. No submission received.

May 2018

DBCTM submitted annual revenue requirement proposal using proposed index.

21 June 2018

QCA approved annual revenue requirement proposal


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