The other notable feature of this graph is that the long-run swings in Australian dollar prices tend to be smaller than those in foreign currency prices.
This is another illustration of the stabilising effects of our floating exchange rate; when commodity prices are high, the exchange rate tends to be high, and when commodity prices are low the exchange rate tends to be low, smoothing out the fluctuations in domestic prices. This provides an important source of stability for the economy as a whole.