Life can be brutal at investment banks. Repeated waves of restructuring and redundancies over the past few years have created an army of paranoid employees who know that they will probably never earn as much money as they are used to – and that a tap on the shoulder from HR could come at any time.

So it is perhaps surprising to see that, when it comes to cost-cutting, investment banks are going round in circles. In the first half of this year, costs across the industry fell by just 1%, according to my analysis of the 14 biggest investment banks. If you look at costs on a trailing 12-month basis, the industry is right back where it started: costs of $165 billion over the past four quarters are the same as in 2009. The problem, and it's a biggy, is that revenues have fallen by more than one fifth since then.