For jaded investors, Armageddon has become the common base on which assumptions rest. Profit warnings occur every day and there is little incentive to buy companies that, while cheap, might just as easily halve in price as double. So the decision by Research In Motion, maker of the addictive BlackBerry phone, to lower expectations was unsurprising, given that the company’s shares have lost three-quarters of their value since June. In fact, this profit warning was not actually that bad.

The low end of management’s forecasts for third quarter revenues was trimmed from $2.95bn to $2.75bn. A third of that downgrade is a result of currency changes while the timing of product launches and the sharp downturn in consumer demand did the rest. Even so, sales will still rise by 65 per cent from the year before.