Last week’s 25th anniversary of Big Bang – the deregulation of the City of London in 1986 – is a good time to ponder whether the investment banking industry can learn anything from the past as it seeks to find a route to a more sustainable future.

A glance through the 1987 accounts for Morgan Grenfell Group, the UK merchant bank that shares its roots with JP Morgan and which was subsumed into Deutsche Bank in 1990, suggests that it can, although the accounts seem almost quaint to modern eyes.