In most companies the chief executive and top managers are the highest-paid employees, but not at investment banks. Over the past two decades, a group of largely unknown traders playing with billions of dollars of their banks’ money have walked away with end-of-year bonuses well above the millions paid to their superiors.

Every year stories emerge of the tens of millions of dollars paid to those working on these proprietary trading desks, such as the rumours four years ago of the £30m (€37m) bonus paid to London-based Goldman Sachs trader Driss Ben-Brahim.