When Manchester United announced the 'club record' signing of Juan Mata this weekend, the Spanish playmaker's £37.1million move from Chelsea didn't sound much like the largest amount of money the Premier League champions had ever spent to bring a player to Old Trafford.
In literal terms, the fee did usurp the £30.75million paid to Tottenham Hotspur for Dimitar Berbatov in 2008, but it doesn't really take into account inflation, and what the historical prices of all player transfers would look like in 'modern money' terms.
Thankfully, a combined study by Paul Tomkins and Graeme Riley has created a Transfer Price Index (TPI), which adjusts traditional valuations to determine each player's the Current Transfer Purchase Price (CTPP) by way of an inflation index.
It makes for some pretty interesting results.
For example, the £50million that Chelsea paid Liverpool for Fernando Torres in January 2011 should not be regarded as the Stamford Bridge club's record transfer, because Andrei Shevchenko's £30.8million move to west London in 2006.
The Ukrainian striker's arrival cost Roman Abramovich - in today's market - the equivalent of £76million, which would make him the most expensive signing in Premier League history in modern money.
Wayne Rooney, Rio Ferdinand and Juan Sebastian Veron's Current Transfer Purchase Price also comes in higher than the fee Manchester United paid for Mata, while Arsenal's summer signing Mesut Ozil cost about the same as what Newcastle United paid Blackburn Rovers for the services of Alan Shearer in 1996.
Click through the tabs above or below to check out the five most expensive inflation-adjusted signings from the biggest spending clubs in the Premier League era!