The Isolation Index

Identifying and providing extra support to isolated schools.

About the Isolation Index

The Isolation Index has been around since 2001 when the Government introduced it as a replacement for Targeted Rural funding. That change meant that for the first time we could measure the relative degree of isolation each school faced. It distinguished between the needs and costs faced by a school 25 minutes' drive from a city compared to one two hours from even the smallest centre.

The Isolation Index is used to determine the relative isolation of schools and early learning services. It currently uses weighted distances from population centres of 5,000 and 20,000 and 100,000 people, based on 2001 census data and old road data. The 20,000 population town is weighted most heavily.

New Zealand’s geography means that schools and early learning services are widely dispersed, and some are long distances from towns. Isolation can mean that there are additional costs that schools face, e.g. it can be further for staff and students to travel, or additional costs for accessing trades and services. To recognise these additional costs, we provide additional funding to isolated schools so that they can operate and deliver the curriculum. The Isolation Index helps us identify these schools.

The Isolation Index is being updated in 2023 to reflect changes in New Zealand over the last 20 years.

From January 2023 we are implementing a new Isolation Index to reflect changes in New Zealand over the last 20 years. The old Isolation Index uses 2001 census data and old road data. Since 2001, the population has increased, and infrastructure improvements have made travel faster and easier. This has lessened the relative isolation of some schools. The Isolation Index is based on the distance from three population centres that have a range of goods and services your schools need. Moderate sized towns are now better able to provide the goods and services needed by schools and some services that previously required travel time can be conducted digitally. The link to the 100,000 population town skews resourcing away from where funding is most needed by those schools that are more remote.

Changes to the Isolation Index

  1. The updated index is calculated using the latest available data from the 2018 census and distance and travel time analysis calculated using 2020 road data.
  2. We are now able to include travel time as well as distance when calculating a school’s isolation. We know that steep windy roads increase isolation and tradespeople providing services to isolated schools often charge for both time and distance. This is a significant change and better reflects the actual isolation experienced by schools and kura.
  3. We are changing the largest population centre from 100,000 to 60,000 based on a better understanding of where isolation is more strongly felt.
  4. There are currently two Isolation Indexes in use for schooling. The Voluntary Bonding Scheme uses a different Isolation Index (using 2006 census data) than Targeted Funding for Isolation, the Property Maintenance Grant and 5 Year Agreement Funding. From January 2023, the new Isolation Index will replace them both.

We are implementing the Equity Index at the same time as the updated Isolation Index. Read more about these changes: The Equity Index.

How the Isolation Index applies to funding

The Isolation Index determines eligibility and affects funding calculations for the operational grant components Targeted Funding for Isolation and the Property Maintenance Grant (isolation component). It is also used for 5 Year Agreement Funding and the Voluntary Bonding Scheme.

From January 2023, a new formula will be used to calculate Targeted Funding for Isolation.

The old formula included a per-pupil component. However, this resulted in smaller, more isolated schools receiving less funding than larger, less isolated schools. We also heard from the sector that isolation costs do not increase with roll size, instead, it was ‘smallness’ that compounded isolation problems. From 2023, eligible schools will receive Targeted Funding for Isolation based on their isolation alone, and no per-pupil amount.

Further information

Further information on operational funding.

If you have any questions or want more information email:

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