Input methodologies

Input methodologies involve setting upfront regulatory methodologies, rules, processes, requirements and evaluation criteria for services that are regulated under Part 4, and for undertaking Part 4 inquiries.

In this section...

The purpose of input methodologies is to promote certainty for suppliers and consumers in relation to the rules, requirements, and processes applying to the regulation, or proposed regulation, of goods or services under Part 4 of the Commerce Act 1986.

Once input methodologies are determined, they apply to both regulated parties and the Commerce Commission.

Input methodologies were determined in December 2010 for specified airport services, electricity distribution and transmission, and gas pipelines. The Commission must review each input methodology no later than seven years after its date of publication and, after that, at intervals of no more than seven years.

Key information

Current determinations, reports and supporting information.

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Input methodologies review

This page includes information on the review of the input methodologies that the Commission must undertake within 7 years of setting the input methodologies.

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Electricity distribution

Input methodologies for electricity distribution services were determined in December 2010.

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The input methodologies determination for Transpower includes input methodologies that apply to individual price-quality regulation and input methodologies that apply to information disclosure regulation.

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Gas pipelines

Input methodologies for gas pipeline services were determined in December 2010.

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Input methodologies for specified airport services supplied by the companies operating Auckland, Christchurch and Wellington International Airports were determined in December 2010.

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Amendments and clarifications

On this page you can find input methodologies related correspondence. From time to time the Commission may also publish updates on process relating to input methodologies.

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Amendments to the WACC percentile


Litigation outcomes related to Input Methdologies determined by the Commission in December 2010.

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