Spreadsheet model

New Zealand Superannuation Fund Contribution Rate Model - HYEFU 2023

Formats and related files

This is the Treasury’s model that is used to calculate the government's capital contribution to the New Zealand Superannuation Fund (NZSF).

The model was updated at the time of the release of the Half Year Economic and Fiscal Update 2023 (HYEFU 2023).

This model, which is in MS Excel workbook format, calculates the contribution rate for pre-funding New Zealand Superannuation (NZS), under the legislated formula in Section 43 of the New Zealand Superannuation and Retirement Income Act 2001. From this contribution rate, which is expressed as a percentage of nominal GDP, the Government’s capital contributions to the Fund, and in later years withdrawals from the Fund to the Crown, are derived. The only exception to this is the contribution for the current fiscal year, 2023/24, which has not been changed from the value calculated at the Budget Economic and Fiscal Update 2023 (BEFU 2023). This is because the monthly payments to the NZSF in this year are based on equal instalments of this annual amount.

Since the last release with the Pre-election Economic and Fiscal Update 2023 (PREFU 2023) the model’s data inputs have been updated. Specifically, the model uses the latest five-year forecasts provided by the NZSF of the Fund’s earnings and tax payments and those of NZS expenses made by the Ministry of Social Development, as well as Treasury’s longer-term projections of nominal GDP and aggregate net (after-tax) NZS expenditure.

For information purposes, the model contains two additional worksheets:

  • NZS data This gives historical data, and the latest forecasts and projections, for aggregate NZS expenditure, both inclusive (gross) and exclusive (net) of tax, and average NZS recipient numbers over fiscal years. Expenditure data is given in nominal dollar terms and as a percentage of nominal GDP.
  • NZSF history This gives historical data on the NZSF since its inception in 2001/02 up to and including the latest historical fiscal year (year ended 30 June).

The projected gross NZS tracks in the NZS data worksheet display a potential path, beyond the latest forecast horizon, of the aggregate NZS expenditure numbers. These are in gross of tax terms, which is how all expenses in the Financial Statements of the Government of New Zealand are recorded.

Much more information about the logic of the NZSF model, the history and purpose of the NZSF itself, the public pension New Zealand Superannuation, and the demographic changes that were a major reason for establishing the NZSF can be found in the Treasury Working Paper Golden Years – Understanding the New Zealand Superannuation Fund.

The MS Excel workbook New Zealand Superannuation Fund (NZSF) Contribution Rate Model is a special purpose document and cannot be supplied in HTML format. The modelling guide in Adobe PDF format can be supplied in HTML format if requested from Information Services.