They have not all gone. But there are fewer of them, with far less clout. Traders once ran the debt markets and filled the upper echelons of the world’s largest and most powerful investment banks. But the global financial crisis of 2007-2008 changed perceptions of risk, and waves of regulation have taken their toll.

The recent volatility across the debt markets and concerns about liquidity have fuelled the debate over how markets should evolve from here.