How the returns work

MMFs quote an annual yield, for example 10%. It is worked out daily and usually added to your balance every month, so your interest earns interest.

• Yields change every day with interest rates. Last month's rate is not a promise.
• Interest is taxed: 15% withholding tax is taken off before it reaches you. A 10% yield is about 8.5% after tax.
• Compare the after-tax yield with inflation. If inflation is 7%, an 8.5% after-tax return means your money is growing in real terms.

Our rates board shows each fund's yield, the after-tax figure and how it moved this week.