Black Monday on August 24 sent global stock markets reeling, forcing US stock exchanges to implement emergency procedures including “circuit breakers”, temporarily halting trading in an attempt to give prices time to stabilise.

Many exchange-traded funds were also hit by the turbulence, their prices falling below those of the underlying shares they are supposed to track. Financial News spoke to Jose Garcia-Zarate, a senior ETF analyst at Morningstar Europe, about the "flash crash".