Civil debt interest rates are legislated in NZ. Civil cases...

Civil debt interest rates are legislated in NZ. Civil cases commenced prior to 1 January 2018 are subject to the Interest on Money Claims Act of 2016 (IOMCA 2016). Cases commenced prior to 1 January 2018 are subject to the Judicature Act 1908 section 87 (JA 1908).

The IOMCA of 2016 prescribes interest due based on observations of 6month Term Deposit rates issued by the Reserve Bank, PLUS a premium of .15% (point one five percent). The JA 1908 prescribed interest due at a fixed rate of 5% (five percent). Around mid 2011 the JA 1908 interest rate was dropped to 5% from 8.4% (eight point four percent)

Currently there is a civil debt calculator on the justice.govt.nz website which calculates interest due based on the Interest on Money Claims Act of 2016. Strangely enough the calculator will only accept a maximum initial amount owed of $10M. Using the calculator for the period 1Jan 2016 - 3May 2019 (today), a NZ$10M debt will have accrued just under $1.19M in interest. Therefore a NZ$40M debt will have accrued 4x this or around NZ$6M interest. Allowing for exchange rates a USD$40M debt would be due interest (for this period) of somewhere around NZ$10M.