Not even God knows the correct price earnings multiple for any given stock at any given time, according to the American academic Burton Malkiel. But the Almighty appears to be having particular trouble working out the right multiple for alternative asset managers.

The recent surge by hedge funds and private equity groups to go public or sell stakes in themselves to private investors, prompted the head of one investment bank in Europe last week to wonder aloud whether in years to come analysts and historians will identify the valuations applied to some of these sales as the point at which a bull run became a bubble.