How far could America’s stockmarket fall?

The sound of alarm bells is becoming harder to ignore. America’s stockmarket finished the first quarter of 2024 on an astonishing tear, with its benchmark S&P 500 index having risen in 18 out of the preceding 22 weeks. No longer: it has fallen over each of the past three. Look at individual stocks, meanwhile, and it is clear just how far investors have swung from euphoria to twitchiness. Nvidia was the poster child of the S&P 500’s winning streak, seeing its share price more than double between October and March. On April 19th it fell by a gut-churning 10% over the course of a single day, wiping more than $200bn from the company’s market value. The awful news that precipitated the plunge? There wasn’t any.

If there is a reason for this attack of the vapours, it is that the prospect of cheaper money is receding into the distance. American consumer prices rose by 3.5% in the year to March. That is far too high for the Federal Reserve to consider cutting interest rates imminently unless something calamitous happens. Thus investors have pared their bets accordingly. But something else is going on, too. As the size of the Nvidia jolt suggests, turning-points have less to do with sober-headed analysis than mob psychology. Markets have recovered a bit in recent days, suggesting plenty of uncertainty. The question now is whether the mood will continue to darken.