The Australian dollar would have been the week's worst-performing major currency had the South African rand not pipped it at the post. It was no coincidence that the four laggards in the weekly league represented commodity-exporting countries. Economic data from China and Euroland gave rise to new worries among investors that global growth might be on the wane. In particular, purchasing managers indices (which rate activity on a scale of 0-100 in which 50 represents neither growth nor shrinkage) came in below 50 for the euro area and China. The numbers were not a great surprise but they were an unwelcome reminder that global growth remains vulnerable and, with it, demand for Australia's coal and iron ore exports.