Compounded ZARONIA period averages and index


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On each business day, the South African Reserve Bank (SARB) publishes compounded averages and index values based on past realisations of the South African Overnight Index Average (ZARONIA) interest rate benchmark. Publishing compounded ZARONIA period averages provides market participants with a single point of reference for backward-looking term rates, including 1-week, 1-month, 3-month, 6-month, 9-month, and 12-month tenors.

The ZARONIA index measures the cumulative effect of compounding ZARONIA on a notional unit of investment over time, with the initial value set to 100.000000000000 on 1 November 2022, the first value date of ZARONIA. Market participants may use the published index values to determine the compounded ZARONIA period average rate that is applicable over their maturities of choice.

The SARB publishes the compounded ZARONIA period averages and index at approximately 10H00, South African time. The calculation methodology and policies governing compounded ZARONIA period averages can be found here.

Compounded averages and index data
Compounded averages and index graph

The South African Reserve Bank (SARB), in so far as it contributes to the determination process of the rates it publishes, takes reasonable measures to ensure the accuracy of the rates. The SARB shall not be liable for any error or inaccuracy in the rate or the information, for any delay in updating the rate or the information, nor shall it be liable or responsible for any reliance on, use of, or inability to use the rate or the information in any commercial activity. The SARB makes no representations or warranties, expressed or implied, as to the rates’ accuracy, timeliness, completeness, merchantability, or fitness for any particular purpose. The SARB accepts no liability or responsibility for any direct or indirect loss, damage, expense, or claim howsoever arising, including but not limited to any such loss or claims which may arise from any act, commission, or omission (negligent or otherwise) on the part of the SARB, its employees and representatives relating to, or in connection with the calculation and/or publishing, or delay in the publishing or republishing of a reference rate, or from the direct or indirect reliance on, use of, or inability to use a rate.