By Kris Voakes, Goal.com
The biggest 10 transfers of 2013 cost the clubs involved a staggering 1.2 billion euros ($1.65 billion), according to new research conducted by Goal.
The Goal Transfer List was compiled to highlight the maximum potential payout for clubs relating to each major transfer over the last 12 months and the results show that spending on elite players has never been higher.
In a year in which the world record transfer fee was broken by Gareth Bale's move to Real Madrid, the total amount committed to salaries, taxes and additional costs saw six deals break the 100 million euro barrier.
Bale's deal proved to be the most expensive of all, with Madrid set to pay out a total of 198.8 million euros if the Welshman sees out his six-year contract in the Spanish capital.
The figures were derived from an amalgamation of all foreseeable costs over the course of each player's contract. Net salary figures were adjusted according to the current tax laws of the applicable country to reach a final gross payable amount.
Signing-on fees and agent fees were then included following consultation with sources and experts in each market, as were additional charges such as administration costs. In all cases, where figures are not publicly available, reasonable estimates have been made.
For those transfers which were subject to conditional bonuses, whether payable to the selling club or to the player, those fees were also added in order to reach the maximum potential cost of each player to their new clubs.
The total costs show a continued growth in the spending habits of clubs at the higher end of the game, with the increased levels of cash coming into football being used to keep the transfer market moving forward at a rapid rate.
Graham Shaw, Goal Editorial Director, said: "The Goal Transfer List is an indication of the continued growth in the popularity of football at the elite end of the game.
"Clubs know that signing top players is essential for them to compete for the huge rewards on offer for success in domestic and international competitions."
The full breakdown of costs for each transfer in the Goal Transfer List is available in our comprehensive slideshow, while there will be a series of features running on Goal relating to the study.