We will now take a look at some interesting data and trends over time from transfers in the Premier League. Our data set contains all of the transfers in the league back to 1992.
We’ll first look at overall spending by club. Unlike major American sports leagues, European soccer is known for large and seemingly unlimited sums of money flowing to build the best teams. The following graph shows total spending in 2019 in the Premier League. A green bar means they profited money from the transfer market, while a red bar indicates that they spent more on players than they received.
Almost all teams spent significantly more than they earned. The story is similar for 2016, 2017, and 2018, shown here:
We see typical clubs float to the top, such as Manchester City, Manchester United, Chelsea, and Liverpool. This large spending wasn’t always the case, however. If we look at spending in 1992, we see a much more even split between clubs that made money from the transfer market, and clubs that lost money from the transfer market.
To illustrate this further, we look at the average spending of all clubs in the transfer market from 1992 to 2019.
As we can see, the total amount spent has increased exponentially since 1992. This shows the need to recognize important trends in the transfer market and optimize value. Teams are spending so much money in today’s game in the transfer market.
Next, we’ll look at the relationship between age of the players and their transfer fees. Do clubs tend to pay more for older, experienced players, or young rising talent? We can plot age against transfer fee for the years 2017, 2018, and 2019:
All three of these plots follow a similar, bell shaped pattern. That is, the most expensive transfers tend to be neither young nor old. This makes sense, as middle aged players have proven experience and are in the primes of their career. Young players are a risk, which deflates their price, and old players are injury prone and past their physical prime. It is interesting to note, however, that the younger end of the spectrum actually tends to command higher transfer fees than the older end of the spectrum. This suggests that the MLS league’s strategy of purchasing old stars about to retire as an optimal strategy to getting the best players to boost their league for the least amount of money.
Finally, we will look at the flow of players through the major leagues. Do players typically transfer to other clubs within the same league or to completely different leagues? Is talent pouring into one particular league? We can answer questions like these using a chord diagram. This is a circular data visualization tool to see the transfers between all of the different leagues.
We can draw a few conclusions from this graph. The first is that the Premier League, more than any other league, transfers players between other leagues, rather than between clubs within the league. It also does not do as many transfers between the major leagues as the Spanish league, the French league, or the Italian league. It does about the same amount of transfers as the German league. Finally, the biggest leagues that it transfers players to and from is the Championship league and the Spanish league.