On the eve of the new Premier League season we’ve produced a graphic to illustrate how each team’s squad has changed and how their players were used last term.

First of all we came up with a headline measure for continuity: of all the minutes played across a club’s squad in league matches last season, what percentage were accumulated by players who are still at the club? This gives us a more reliable measure than just counting players, as it will be dented more by a first team regular leaving than by the departure of a fringe player.

We also wanted to see what else we could get into our graphic without cluttering it and decided to look at to what extent each club relied on a core of players. We counted how many players had represented their clubs for at least 25% of possible league minutes, which felt like a sensible definition of a ‘first team’ player. Counting how many players met this criterion for each club gives us a useful measure of squad rotation and we can also count how many of these have remained at the club.

Finally we added in a measure of what percentage of the club’s total league minutes had been accumulated by their 11 most-used players last season, which gives us a different way of looking at how much or little each manager rotated their squad.

Observations:

Newcastle rotated their squad the most heavily last season – they were the only side whose most-used eleven players racked up less than two thirds of the club’s total minutes on the pitch. Manchester United and Hull also stand out here.

In contrast we can see the extent to which Sunderland, Everton and Crystal Palace relied on a small core of players. This could well spell problems for the Black Cats who’ve lost the most first team players (6) from last season and consequently sit at the foot of our graphic – their new recruits will have to gel quickly if they’re to improve on last season’s campaign.

Only the 3 sides at the top of this graphic have managed to hold on to every player who featured regularly last season, and surprisingly all of them – Southampton, Man Utd and Chelsea – have undergone recent managerial changes.

While there’s been reasonably high turnover at newly-promoted Hull and Crystal Palace, champions Cardiff look to have largely kept faith with the squad who got them up.