Producer prices have fallen due to lower dairy and power prices.
Official figures show producers input prices fell 0.3 percent in the three months to June, compared with the previous quarter.
The prices producers charged their customers fell 0.2 percent.
Producer prices have fallen in each of the past five quarters.
Lower input prices have been driven by a 4 percent fall in dairy manufacturing prices, and a 9 percent fall in electricity and gas prices, due to cheap hydro power supplies.
The construction industry faced higher input and output costs, because of a rise in the cost of building new houses.
Separately, the capital goods price index rose 0.6 percent, 2.7 percent higher than the previous year.
