Kincella, here is the answer to your question compliments of the RBA
"Currently, credit to the household sector is growing … well in excess of what could be considered sustainable in the medium to longer term. Much of this is … fuelling a rate of housing price increases of the order of 20-25% …. The risk presented by these developments is that, the longer they go on, the larger will be the contractionary effect on the economy when they inevitably turn’ – Statement on Monetary Policy, 11 August 2003