Commodity prices posted their 13th consecutive monthly rise in August, driven by price increases in iron ore and coal.
The prices of wheat and barley also rose sharply.
The Reserve Bank of Australia's (RBA) index of commodity prices in special drawing rights (SDR) terms rose 2.7 per cent to 121.4 points in August, according to preliminary estimates released by the RBA on Wednesday.
It's the highest reading since the index series began in July 1982.
The latest rise means the index in August has risen 53 per cent over the past year in SDR terms.
The value of the SDR is calculated by the International Monetary Fund (IMF) on the basis of a weighted basket of four currencies: US dollar, euro, Japanese yen, and UK pound.
"Much of this rise has been due to increases in iron ore, coking coal and thermal coal export prices, although all components of the index increased over this period," the RBA said in a statement.
"With the appreciation of the exchange rate over the year, the index rose by 38 per cent in Australian dollar terms."
The index has risen every month since the May 2009, with the exception of a fall in July last year.
The largest contributors to the rise in SDR terms in August were increases in the prices of iron ore and coal.
The readings for the index for recent months used preliminary estimates from market information for iron ore, coking coal and thermal coal export prices.
In Australian dollar terms, the index rose 0.8 per cent in August following and increase of 2.1 per cent in July.
