The Australian dollar plunged on official statistics showing a weaker local economy.
The ABS announced just a 0.3% rise in GDP for the September quarters.
This means the economy grew only 2.7% for the year, compared to 3.2% previously.
Westpac economists said the headline GDP reading sparked a quick slide under 0.8410.
The Aussie then extended its decline to 0.8392 within 20 minutes.
The next obvious target on AUD/USD is 0.8360/70.