Some important notes need to be made on methodology. The first six editions of this report, published annually from 2010 to 2015 inclusive, were released in Spring, usually April, and included salaries either for the ‘active’ or most recently completed season for each league at the time of publication.
For the European football leagues up to the 2015 report, completed seasons were used. But a wider knowledge base and more established access to better data gave us the confidence to use ‘live’ data for all the European football leagues from the GSSS 2016 onwards.
As the title of the report says, our numbers are compiled by survey. More accurately they are the result of an analysis and organisation of data either A) established as fact in those leagues where minutiae are in the public domain; or B) gathered by survey methods from a multitude of knowledgeable sources, more of which in a moment.
As ever, all the numbers can only ever be a snapshot of a situation at a point in time, whether the opening day of a season or the day after a transfer window has closed.
All figures (across all leagues) are sourced directly or indirectly from one or more of unions, player associations, players themselves, agents, leagues, clubs and / or club sources, and other reliable administrative bodies.
To be more specific, league by league, from the wealthiest league down: the NBA numbers are in the public domain, so too the IPL figures (via auctions, and club sources filling gaps) and the MLB numbers.
For the Premier League, and all the other European football leagues (in Spain, Germany, Italy, France, Scotland) we source a specific number for each and every individual player wherever possible, either from players themselves, their agents or other representatives, or club sources.
It is a painstaking exercise and the findings can, by a survey’s definition, only be as accurate as the information provided. There are ‘backstops’ however, including public domain sources, not all widely known, that give a good indication of general financial situations. And there are sources not in the public domain. One example: Sportingintelligence has undertaken consultancy and advisory work over a number of years for quantum claims (for loss of earnings in football, mostly because of injury) that has involved access to numerous player contracts, which can be corroborative. All data on individuals for the GSSS reports is gathered on a confidential basis - hence why we don’t publish individual player salary information.