Manchester United worth $1billion less than when Louis van Gaal took over as manager

"Football clubs typically don’t present a particularly attractive investment proposition because their revenues are lumpy, and their employees are rather expensive," said stock market analyst Laith Khalaf.

"Mistakes on the pitch can be costly for shareholders too – in 2015 Manchester United’s broadcast revenues dropped by £30 million as it failed to qualify for the Champions League in that season. So far this year things seem to be picking up with a bounce in revenues, but if the club fails to qualify for the Champions League this season, next year could be a fallow one for investors."