By The Numbers: Premier League Penalties
This season, no game week has seen more than four penalties scored. So far, up to the evening of Monday of GW33, 75 penalties have been scored this season. As we saw a few weeks back roughly 82-84% of penalties won are scored in the Premier League historically, and the ratio is consistent. This season has also seen the highest goals per game ratio of the Premier League so far. Indeed, this rate is increasing slightly: as of GW32, when the video that accompanies this piece was prepared, the rate was 2.82 goals per game. As the hunt for top four places and to avoid relegation heats up, we might expect the scoring to drop off slightly as teams make a final concerted effort to tighten up; on the other hand, with some teams having nothing left to play for, this could increase. If it does, or indeed holds, we are looking at a record-breaking Premier League season for goals.
Top 5 PL seasons goal per game
It is also one of only five seasons where there have been 0.2 penalties or more scored per game. Two of the seasons, this season and 2010/11, appear in both lists.
Top 5 PL seasons penalties per game
|Season||Goals (penalties)||Games Played||PPG|
The average number of penalties scored per game from 1992/93 to the present day is 0.17. Only the 1999/2000 season, where 2.79 goals per game were scored, saw an average number of penalties per game. Otherwise, the top 10 seasons for goals per game saw an above average number of penalties per game, with the sole exception of 1997/1998, which saw 0.18 penalties per game.
Top 10 seasons for GPP showing PPG
The average percentage of goals scored in a season that are penalties, as opposed to shots or headers or free-kicks, is 6.58%. The lowest season was 2001/02, with a paltry 4.8% of goals scored being penalties, followed by the first ever Premier League season 1992/93, which saw 4.99% of goals scored being penalties.
The highest proportion of goals scored as penalties was the 2006/07 season, which also saw the highest total overall of penalties scored in one season, 87. With a further 57 Premier League matches to play, at the current rate 2016/17 could eclipse 2006/07’s total: at the current rate of 0.23 penalties scored by game, the next 57 could be expected to yield 13 penalties, for a total of 88. Indeed, next is the current season, showing again that teams like Liverpool and Bournemouth are enjoying a bonanza of goals in a season in which penalties seem easier to win.
Top 5 seasons for % penalty goals of goals total
|Season||% of goals as pens|
Because – and this is crucial – penalties seem to be easier to win in some seasons. Penalties are discrete events, awarded at the say-so of the referee, while goals can come from a multitude of sources. Assuming, as we have, that penalties are scored at a fairly consistent rate, we might assume that seasons that see a lot of goals also see a lot of penalties.
That would intuitively make sense as penalties are a form of goal and attacking play creates both goals and the chance to win and hence score penalties. Weak defences seem likely to make mistakes that lead to goals, just as they might well make mistakes that lead to the concession of penalties. Weak defences are also badly organised, leading to scrambles and last-ditch tackles, again another chance to win penalties.
But, interestingly, there is only a weak correlation between the two, between overall goals per game scored and penalties per game scored. It is a positive correlation, but not one that would make any statistician accept anything more than a weak link. In other words, lots of goals is no guarantee that lots of those goals are penalties.
Weirder still, there is a weak negative correlation between penalties scored and fouls won. This means that as fouls increase, the number of penalties scored actually goes down, albeit with a limited relationship between the two sets of data.
If we look at the 14 seasons for which we have fouls per game data, we can see that the two seasons with the most fouls have an average or below average penalties per game, and the three seasons with the fewest fouls per game have slightly above average penalty per game counts.
|Season||Fouls per game||PPG|
In other words, the two things that would most intuitively indicate why a lot of penalties are being scored, overall goal scoring and fouling, do not, in fact, show a strong correlation to the number of penalties scored.
So, whatever the reasons for plenty of penalties being scored, there’s no easy way to predict it in relation to other data.