Looking at this website that archives exchange rates:
http://www.gocurrency.com/index.htm
exactly 3 months ago (July 10th) to now (Oct 10th)

US$ 0.96 - 0.67 (down 29 or 30.2%)
£ 0.48 - 0.39 (down 9 or 18.75%)
¥ 103 - 66 (down 37 or 35.9%)
EU€ 0.60 - 0.49 (down 11 or 18.3%)
NZ$ 1.27 - 1.12 (down 0.15 or 11.8%)

We're even weakening to the NZ$, how pathetic does that make the AU$ if a 'more troubled economy' like NZ is doing better than we are on the cross-rates.
Every currency I checked had the AU$ dropping by 10-30% in the last 3 months, suggesting that it was either overvalued before (July was the peak) or now just unwanted.
Hell, even Zimbabwe is probably doing better than us...