Gulp. That is the sound of US Treasury investors eyeing the $200bn (€136bn) in new supply the market must digest this week. Government support of the economy in the crisis has resulted in record auction sizes and, so far, the market has coped well. There is little to suggest any imminent problem.

But this latest wave of borrowing comes as investors are considering a whole series of questions fundamental to future market direction. Put this together with a two-day rate-setting meeting at the Federal Reserve, beginning on Tuesday, and this week could prove testing for the market.