ANZ is predicting that the high New Zealand dollar will continue to eat into exporters' returns.
The ANZ latest commodity price index found prices eased 0.5% in July.
ANZ economist Mark Smith says the persistently strong currency is reducing producer returns.
He says usually the exchange rate buffers commodity price movements, so when the commodity price falls so does the New Zealand dollar.
But Mr Smith says in July the New Zealand dollar actually strengthened so New Zealand dollar returns were 3.1% lower that month.
He says that means that exporters will be looking nervously not only at the global economy, but also what the New Zealand dollar does.
Mr Smith says normally the currency tends to follow commodity prices, but the disconnect that emerged in July suggests that the New Zealand dollar is not being driven solely by commodity prices.