When it comes to leaving a city, companies and markets are very different creatures. Companies will shift from one global city to another in search of a more favourable tax regime or more beneficial employment law. For markets — particularly complex ones with strategic functions — it is much harder to move wholesale. The City of London is such a market.

Given London’s uncertain status following the Brexit vote, the predictions about the effect on Hong Kong’s financial market when China was about to take over sovereignty from the British in 1997 are useful. Beijing aimed to make Shanghai China’s main financial centre. The idea was that important Hong Kong markets would migrate to the mainland. That did not happen. Hong Kong is still China’s most international and strongest market. Shanghai, meanwhile, did expand as a financial centre but one geared more towards domestic investors.

One possible outcome for London of leaving the EU is that more routine functions, such as euro clearing, move elsewhere while the more complex markets remain. This possibility is supported by the fact that vital to the more complex London markets are strategic intermediate functions that depend on a mix of very specific types of companies and skills. This is a deeply networked function — that is, companies need each other because each individual company has only partial knowledge or highly specialist capabilities. No single business can give the leading financial centres everything it needs, as the corporate behemoths than once ruled these economies did in the 1960s and 1970s.