Financial innovation, in the form of new investment strategies and products such as equity and credit derivatives, has been one of the hallmarks of global markets since the Black Monday crash of 1987.

But while many of these products have been hailed as ways to disperse market risk, they have also raised concerns that they could help to accelerate a fall in the event of another crash. Twenty years ago, equity futures and options were already established as popular investment tools. Jerry Corrigan, then president of the New York Federal Reserve and now at Goldman Sachs, says the way such products were used in the run-up to the crash set a new paradigm for financial crises.