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The possibility to play a significant number of matches since the start of the professional career is a key success factor for football players. For the first time, issue number 126 of the CIES Football Observatory Big-5 Weekly Post unveils the rankings of teams who played the most important role in the development of current big-5 league players.

In total, the 2,165 footballers fielded so far by big-5 league teams have played in 1,276 clubs from the start of their career at adult level to their 23rd birthday. At the top of the table of teams having contributed most to the development of these players is Real Madrid Castilla. Up until 23 years of age, 45 footballers under contract with big-5 league teams have played for the team currently coached by Zinédine Zidane. Among them, we notably find Juan Mata (Manchester United), Alvaro Negredo (Valencia) and Roberto Soldado (Villarreal).

For comparability reasons, the player development index only considers domestic league games. A match played before the age of 21 is weighted double with respect to a game played between 21 and 23 years of age. Moreover, the values are weighted according to the current employment rate of players in order to give more weight to teams having developed the most fielded footballers.

The team who contributed most to the development of Premier League players is Southampton, followed by Aston Villa and Dutch side Ajax Amsterdam. Chelsea and Everton also rank in the top five positions.

At the top of the tables in the remaining big-5 leagues are Empoli for Italian Serie A players, Bayer Leverkusen for German Bundesliga, Barcelona B for Spanish Liga and Olympique Lyonnais for French Ligue 1 footballers. Issue number 126 of the CIES Football Observatory Big-5 Weekly Post presents the data for the top 40 clubs per league.

The player development index could be particularly useful for leagues, national associations and international football governing bodies to set up systems of financial equalisation and/or reward mechanisms incentivising more teams to promote both the training and fielding of young talents. Over the long term, this would have a positive effect on football as a whole.

The CIES Football Observatory is happy to remind that the updated version of the Digital Atlas on 31 top division European leagues is now available. This unique tool allows you to grasp the latest trends in the football players’ labour market and to situate your favourite club and league within the European context.

The CIES Football Observatory Digital Atlas presents league and club rankings for eight indicators:

  • Average age: the oldest top division league in Europe is Turkey (27.3 years), while the youngest is Croatia (23.9 years). At club level, Chievo Verona is composed of the oldest players (30.6 years). Hajduk Split and Senica have the youngest squad (22.1 years).
  • Average height: the tallest top division leagues at European level are in Germany and Croatia (183.3 cm). The shortest players are to be found in Israel (180.1 cm). There is a 9 cm gap between the tallest and shortest club: Wolfsburg (187.0 cm) and Ludogorets Razgrad (178.0 cm).
  • Average stay: the most stable league from a player turnover perspective is England. Squad members have been in the first team of their employer team for 2.82 years on average. At the opposite end of the table is Serbia (1.71 years). The most and least stable clubs are CSKA Moskow (5.7 years) and Chornomorets Odessa (1.2 years).
  • New signings: clubs in Romania signed the most players since January 1st 2015: 14 per club on average. At the other end of the spectrum is Sweden (7.4 players). At club level, the record high was recorded at Bologna (23 players), while the record low was measured for Karpaty Lviv and Metalurg Zaporizhya (1 player).
  • Debutants: on average, European top division clubs launched 1.04 players without previous experience in the professional game: from 2.29 in Ukraine to 0.13 in Greece. Metalurg Zaporizhya holds the record at club level with 11 debutants. However, they are currently at the bottom of the Ukrainian Premier League table.
  • Club-trained: the top division league in Belarus has the highest percentage of club-trained players (34.0%). Inversely, in Turkey, players who have been in their employer club for at least three seasons between the ages of 15 and 21 only account for 8.3% of squad members. The record high at club level was observed at Gomel (91.7%). More information is presented in the ninth edition of the CIES Football Observatory Monthly Report.
  • Expatriates: the top division league with the highest percentage of expatriate players is that of Cyprus (66.4%). The lowest proportion of expatriates was recorded in Serbia (15.7%). Expatriate footballers account for up to 88.0% of squad members at Slovenian side NK Zavrč. Only three teams out of 460 have no expatriates: HIFK Helsinki, FK Gomel and FK Příbram.
  • Active internationals: the English Premier League gathers the highest percentage of players with national A-team caps since the start of the season (41.4%). This percentage is only 2.0% in Slovenia. The club composed of the greatest proportion of active internationals is Manchester United (72.0%).

The latest Monthly Report of the CIES Football Observatory analyses the presence of club-trained players in 460 teams of 31 top division leagues in UEFA member associations. The study notably shows that the percentage of home-grown footballers in squads has decreased for the sixth consecutive season to reach a new record low.

Following UEFA’s definition, club-trained players are footballers who have been for at least three seasons between the ages of 15 and 21 in their employer team. The relative presence of this category of players in squads has steadily decreased from 23.1% in 2009 to only 19.7% in 2015. Club-trained footballers still accounted for more than one fifth of squad members in 2014: 21.0%.

This finding reflects the lesser tendency of European top division clubs to give their chance to players from their youth academy. As a consequence, the average age of footballers in the 31 top division leagues surveyed has reached a new record high: 26.0 years. The decrease in the proportion of club-trained players also reflects the greater mobility of footballers from their youngest age.

The Report also presents the rankings of clubs who trained the most players active in the leagues surveyed. At the top of the overall table is Partizan Belgrade (78 players trained), followed by Ajax Amsterdam (75 players). FC Barcelona heads the ranking of clubs who trained the most players under contract with big-5 league teams (44 players), ahead of Olympique Lyonnais (35 players) and Real Madrid (34 players). All data is available in issue number 125 of the Big-5 Weekly Post.

Last but not least, the CIES Football Observatory is pleased to unveil a brand new version of its exclusive Digital Atlas on the demography of footballers in Europe. This unique tool presents a wide array of indicators allowing users to grasp the latest trends in the European football players’ labour market. The next Monthly Reports will further develop some of the exclusive information presented in the Digital Atlas.

The CIES Football Observatory is happy to disclose the rankings of the best performing players since the start of the big-5 league season. At the head of the tables for the five field positions considered are Otamendi (centre backs), Aurier (full backs), Cazorla (defensive midfielders), Özil (attacking midfielders) and Lewandowski (forwards). The top 10 tables per position are presented in issue number 124 of the Big-5 Weekly Post.

The first position held by Otamendi in the centre back table is mainly related to his outstanding skills in the area of rigour (see explanation below). At full back level, Aurier performed particularly well from a recovery perspective. Cazorla outranks all defensive midfielders mainly thanks to his statistics in the area of distribution. Among attacking midfielders, Özil has no rivals in terms of chance creation. Finally, shooting is the key strength of Lewandowski compared to other forwards.

The rankings are based on a purely data-driven and objective methodology developed by the CIES Football Observatory research team. The Key Performance Indicators (KPIs) considered measure players’ productivity in six complementary areas of the game. The final score is the sum of values measured in each area, weighted according to the importance of the latter for a given position. Only players fielded for at least 60% of domestic league minutes are included in the rankings.

A thorough presentation of the CIES Football Observatory approach for the technical analysis of performance is available in the fifth edition of the Monthly Report.

CIES Football Observatory KPIs

  • Rigour: ability to minimise goal opportunities for opponents through effective duelling.
  • Recovery: ability to minimise goal opportunities for opponents through proficient interception work.
  • Distribution: ability to keep a hold on the game through efficient passing.
  • Take on: ability to create dangerous situations by successfully challenging opponents.
  • Chance creation: ability to put teammates in a favourable position to strike.
  • Shooting: ability to take advantage of goal opportunities through accurate shooting.

Tottenham Hotspur tops the Premier League table of clubs who fielded the youngest players: 24.7 years on average. This is the fourth lowest figure at big-5 league level after Nice (24.1), Valencia (24.5) and Bayer Leverkusen (24.5). All data is available in issue number 123 of the Big-5 Weekly Post.

At second and third position in the English Premier League ranking are Liverpool (25.5 years) and Newcastle (25.6). In contrast, the average age on the pitch is particularly high at West Bromwich Albion (29.2) and Manchester City (28.5).

The oldest teams in the other big-5 leagues are Rayo Vallecano (29.0 years), Bastia (28.6), Darmstadt (28.1) and Chievo (30.7). The average per league varies between 26.3 years in the German Bundesliga and 27.5 years in the Italian Serie A.

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