Sunday, August 3, 2025

English league football mini app

Trends in English football

Welcome to this mini-app where you can see some of the trends in English football over the last 137 years and explore the data for yourself. Almost all the charts are interactive; you can turn chart lines on or off, select different years, or zoom in and explore the data. The legends are almost all interactive (just click on them to see), and almost all plots have a tool menu on the right hand side you can use to explore. Some plots have a widget you can use to change the year.

The league names have changed over the years, but the pyramid structure hasn't. Currently, the Premier League is the top tier (tier 1), but before 1993, the top league was called the First Division. To analyze what's going on over time, it's better to focus on league tiers rather than league names.

Click on a tab to get started!

     

What fraction of matches end in a drawer? The chart below shows the fraction of all matches in a season that ended in a drawer by league and by season. The salmon colored bands show the First and Second World Wars where football was either suspended or played differently.



The league started with a low fraction of draws. That's kind of what you might expect of a new league with a range of club abilities. As football professionalized and lower leagues were established, clubs became more equal up to the end of the second world war. After about 1970, the draw fraction stabilized at about 0.27 for all leagues, except the top league. Since the creation of the Premier League in 1993, the tier 1 draw fraction has dropped, meaning more matches are ending in a win/loss rather than a draw. The question is, why?


There are at least two explanation for the declining draw fraction in the Premier League:

  • The clubs in the league are becoming more unequal.
  • The clubs are still equal, but the style of play has changed, leading to more wins and losses, but still the same number of wins for each team overall.

Fortunately, there is a way of digging into this. Each club will win a fraction of games per season. If the clubs are equal, then the variance or standard deviation will be low, if they're unequal, then the standard deviation (or variance) will be larger. A change in the win fraction standard deviation tells us what's going on. If it's increasing, then the teams are becoming less equal. Let's look at the data.



The data clearly shows an increasing win fraction standard deviation for the Premier League, but not the other leagues. This implies the Premier League is becoming a league of winners and losers, but that's not the case for the other leagues.

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