It ought to have been a matter of investor indifference. The US Federal Reserve raised interest rates by a quarter of a percentage point this week, just as everyone was expecting and just as it had done at its previous six meetings.

But the market was far more interested in what the Fed said than what it did. On this count, the tone was more ominous. The Fed maintained its reference to the "measured" pace of rate increases but added that "pressures on inflation have picked up in recent months and pricing power is more evident".