The country's purchasing power with the rest of the world has weakened further.
Official data shows the terms of trade, which measures the amount of imports that can be bought with a given amount of exports, fell 2 percent in the December quarter.
That was due to export prices falling more than import prices.
It follows a 3.8 percent fall in the September quarter.
Compared with a year ago, the terms of trade are down just over 3 percent.
Both export and import prices fell in the latest period, led by a 13 percent fall in dairy export prices, while petroleum was cheaper to import.