It may appear as no more than a popular children's toy, but investors were able to secure a better return buying Lego sets over the past 15 years than from the stock market, gold or bank accounts, a Telegraph analysis found.

The value of the FTSE 100 is no higher than it was in February 2000, meaning the average annual return to savers over the past decade and half is just 4.1 per cent once dividend payouts are included.

By contrast, Lego sets kept in pristine condition have increased in value 12 per cent each year since the turn of the Millennium, with second-hand prices rising for specific sets as soon as they go out of production. Modern sets are performing even more strongly, with those released last year already selling on eBay for 36 per cent more than their original price.