The Australian and New Zealand dollars slumped on Wednesday as scepticism grew about top trading partner China's stimulus, while the greenback hovered near two-month peaks versus major peers on wagers U.S. interest rate cuts will be gradual. New Zealand's currency was weighed down further by data showing cooling inflation, keeping the door open for aggressive easing by the nation's central bank. The New Zealand dollar sank as much as 0.69% to $0.6041, a level last seen on Aug. 19.