Export prices continued to fall last month, according to ANZ's commodity price index, suggesting the terms of trade's 37-year high may be about as good as it gets.
The ANZ index fell 1.2 per cent last month, making a cumulative decline of 2.5 per cent over the past three months, led by lower world prices for milk powder, logs and aluminium.
Milk powder prices have fallen 16 per cent from their peak in March, ANZ economist Steve Edwards said, while log and aluminium prices have both fallen 11 per cent from their respective peaks in May and April.
Some commodities bucked the trend: apples, kiwifruit, beef, seafood and venison all rose. But twice as many fell - the broadest decline for a year.
However, on average across the month the kiwi dollar was weaker against the currencies of the country's main trading partners, so that in New Zealand dollar terms the ANZ commodity index was unchanged. Over the year to August export commodity prices rose 22 per cent in world price terms, but just 6 per cent in New Zealand dollar terms.