A slump in beef prices has helped drag commodity prices down.
The ANZ Bank Commodity Price Index fell 7.8% in October and is now at an 18 month low.
Nine of 14 commodity prices fell, including double digit declines for beef, wool, skins and aluminium. Dairy prices fell 9.9%.
ANZ economist Steve Edwards says beef recorded the largest fall as US demand fell following the end of the barbecue season.
When converted back into the domestic currency, the weaker New Zealand dollar saw returns to farmers rise 0.7%.