The US Treasury sold $US30 billion of one-month bills at a rate of 0.35%, the highest rate in five years (since 2008) as anxiety rose over whether the US will avert a debt default. Selling also accelerated in US stocks overnight, particularly among those that have run up sharply of late. The Dow Jones is down 1.07%, the S&P 500 is 1.23% lower and the Nasdaq has dropped 2%. SPI futures are down 40 points on Wednesday morning. The IMF has lowered its growth forecast for the global economy and warned the outlook could get bleaker if the US political stand-off over finances drags on.