Chelsea have made £175million from selling academy players since July 2015, the highest of any Premier League side and 21% of the total earned from transfers by the club.
The figures come from the latest CIES' Football Observatory weekly post and name striker Tammy Abraham, who last summer moved to Roma, as the most profitable sale.
On the flip side the West London club have four current players who were the highest academy sales from their previous clubs: Ben Chilwell of Leicester City, Kai Havertz of Bayer Leverkusen, Kepa Arrizabalaga of Athletic Club and Christian Pulisic of Borussia Dortmund.
