Stock splits are a curiously arid exercise. Take a $1,000 share, divide it into two $500 shares and neither the company nor the investors’ stake will change in value. Yet both Apple and Tesla’s equity valuations have jumped since they announced plans to give investors extra shares for each one they hold. On Wednesday, Apple became the first US company to be valued at $2tn. Apple’s rise was aided by strong results. Still, expect to see a wave of copycat splits.

Stock splits were last popular in the 1980s and 1990s, partly as a way to make purchasing round lots of 100 shares more affordable. They are a wink in the direction of retail investors who may not have the funds to buy a single $467 Apple share or $1,887 Tesla share.

In theory this should not matter. Fractional trading on online trading apps such as Robinhood let investors buy partial shares of stock. Yet since announcing a four-for-one stock split, Apple’s shares are up 20 per cent. Tesla’s share price has jumped more than a third to hit a new high since it declared plans for its own five-for-one split.