A basket of New Zealand export commodity prices fell 4 per cent last month to be 2.8 per cent below its level a year ago.
Dairy products, which comprise 47 per cent of the ANZ commodity price index, accounted for three of the four largest falls — butter fell 14 per cent, skim milk powder 12 per cent and whole milk powder 10 per cent.
Pelt prices fell 14 per cent, cheese prices 4 per cent and beef prices 1 per cent.
"It was not all one-way traffic, however, with six commodities posting a lift in prices," said ANZ economist Steve Edwards.
"Aluminium prices recorded the largest increase, lifting 6 per cent followed by sheepmeat prices which rose 3 per cent. The prices of wood pulp, seafood and wool all increased 1 per cent, and lumber prices nudged up a quarter of 1 per cent."