The Australian dollar is one of the most traded currencies in the world, despite Australia being a mid-sized economy. Its role as a "commodity currency" — closely correlated with iron ore, coal, and LNG prices — makes it a barometer for global risk appetite and Chinese economic activity as much as for Australian fundamentals. Understanding what drives the AUD is essential for anyone thinking seriously about the Australian economic outlook.
The Commodity Link
Australia's terms of trade — the ratio of export prices to import prices — has a strong empirical relationship with the AUD/USD exchange rate. When iron ore prices are high and commodity exports are booming, the dollar tends to appreciate. This relationship has been somewhat less reliable in recent years as capital flows and risk sentiment have become more influential drivers, but the commodity link remains the dominant long-run determinant.
The Interest Rate Differential
The difference between Australian and US interest rates significantly influences capital flows and therefore the exchange rate. When Australian rates are higher than US rates, international investors are attracted to Australian dollar assets, supporting the currency. As the US Federal Reserve has held rates higher for longer, this differential has compressed, removing a support that had previously helped the AUD. The expected trajectory of RBA and Fed policy through 2025 will be a key driver.
What a Weaker AUD Means
A lower AUD makes Australian exports cheaper in foreign currency terms (good for exporters and tourism) while making imports more expensive (bad for inflation and consumer purchasing power). The net effect on the economy depends on the composition of trade and consumption. For the RBA, a weaker currency adds to imported inflation — a consideration that complicates monetary easing when the exchange rate is falling simultaneously with interest rates.
