Next week marks 30 years since the infamous “Black Monday” stock market crash of 1987, when the FTSE 100 fell by more than 20pc over the course of a few days.

October 19 and October 20 that year remain the two biggest one-day falls in the history of the FTSE 100, and the only two to top 10pc.

Now, three decades later, the unexpected violence of the market collapse remains seared into the minds of many investors who lived through it.

Black Monday came at the beginning of an investing revolution that was rapidly extending the general population’s access to stock market investing.

In 1987, the Conservative Party’s election manifesto promised to “extend as widely as possible” the opportunity for the public to build up capital, through – among other things – making it easier for everyday people to “buy shares in British industry”.

Great swathes of the economy were privatised during the Eighties, opening up firms such as Jaguar, BT and BP to private investors, often at attractive prices.

These businesses were familiar and many investors were customers, so they provided a natural first step into the world of investing for millions of British savers.

In 1986, the London market was deregulated and switched to electronic trading. Following this “Big Bang”, trading costs fell as competition between financial institutions increased, and the volume of share trading soared.