The administration of President George W. Bush has remained relentlessly optimistic about the outlook for the US economy. Brushing off the recent spate of weak data by arguing that a similar slowdown at the same time last year was followed by a strong resurgence, Carlos Gutierrez, the commerce secretary, told reporters yesterday that there was "a very healthy momentum to the economy".

But what initially seemed to be a short-lived "soft patch" - much like the blip in growth last spring - is now looking a little more ominous.