Tech stocks still have room to grow

At the height of the dotcom boom in the late 1990s, investment guru Michael Mauboussin asked rhetorically whether it was rational that Amazon had a market value four times that of booksellers Borders and Barnes & Noble combined. In retrospect, this valuation proved far too low, as James Anderson, manager of Scottish Mortgage Trust, points out. Amazon’s share price has subsequently soared and the firm’s shares have now risen by more than 50,000% since it listed on the stockmarket 20 years ago. Borders, meanwhile, has gone bust.

Yet Amazon’s recent purchase of food retailer [...]