Banks should consider adding a new disclaimer to their next earnings statement. “Warning: these results are not intended in any way to reflect the underlying performance of our business. Any resemblance between the reported numbers in our securities business and its actual results is entirely unintentional.”

Last week this column warned that investment banks faced a nuclear winter after a brutal third quarter, forecasting that revenues could fall by around one third from the second quarter, and that pre-tax profits would fall by around half.