Specifically, the Swiss number crunchers' data ranks teams from 72 top divisions worldwide according to the average age of their lineups fielded in league fixtures so far this season, combined with the percentage of minutes given to players yet to turn 21 during those games.
When it comes to Europe's "Big Five" alone, the ranking is topped by French side AS Monaco, who boast an average team age of 24.31 years so far this campaign. According to the report, 14.2% of the minutes clocked up by Monaco players this season have been by those under the age of 21.
Here's five key takeaways from the latest CIES report.
Vive la France
Taking just Europe's "Big Five" leagues into account, France's Ligue 1 leads the way in terms of game time offered to young players. Monaco top the ranking with young talents like Myron Boadu, Sofiane Diop, Anthony Musaba and Aurelien Tchouameni in their youthful side this season. Monaco are joined in the top five by Saint-Etienne and Brest with average team ages of 24.74 and 24.75 years respectively. Elsewhere, Marseille (24.81 years), Reims (24.88) and Nice (24.94) ensure that there are six French clubs inside the top 10.
Metta is better
Looking at the wider picture, CIES' overall world ranking is topped by Latvian side FK Metta, who have an incredibly low average team age of just 20.16 years, with 63.5% of minutes in their 21 games given to players yet to turn 21 years old. The oldest player in FK Metta's first-team squad is 22-year-old centre-back Krists Gulbis, who is practically a grizzled veteran compared to some of his teammates.
Arsenal's young guns
0⃣4⃣ passes— Arsenal (@Arsenal) September 26, 2021
0⃣1⃣ knee slide
Liquid football 😍 pic.twitter.com/wo4M4g3esJ
Arsenal's reputation for blooding young players is upheld by the CIES data, with the Gunners boasting the lowest average-age team (25.01 years) in the Premier League. This was symbolised at the weekend as young midfielders Emile Smith Rowe (21) and Martin Odegaard (22) ran local rivals Tottenham Hotspur ragged in an emphatic 3-1 win. The report found that 11% of league minutes played for Arsenal have been shared between U21 talent such as Bukayo Saka, Gabriel Martinelli and Folarin Balogun.
Barcelona are getting something right
A year later, he's back scoring goals... 🥰— LaLiga English (@LaLigaEN) September 27, 2021
💙 @ANSUFATI ❤️
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Following a summer of chaos, Barca have struggled for consistency so far this season. However, the Catalans can at least take a sliver of solace from the fact that their proud history of transforming young academy hopefuls into first-team stars appears to remain on track. Ronald Koeman's side are ranked second in Europe's top five leagues for the percentage of minutes handed to players under the age of 21 with a total of 22.7% thanks to young stars like Ansu Fati, Pedri and Gavi. The only club above them on the list is Bayer Leverkusen of Germany, who have accrued a total of 23.5% in Bundesliga games this campaign.
The 0.0% Club
At the other end of the spectrum, 89 of the 1,041 teams surveyed have not fielded any players under the age of 21 so far this season including Juventus and Atletico Madrid. Newcastle United, Burnley and West Ham United are the Premier League clubs to not yet include any U21 players in their team in 2021-22, and the same goes for German duo Wolfsburg and Eintracht Frankfurt as well as Scottish champions Rangers.