Simple question: Have Arsenal progressed this year? Are they better than they were last year? To answer these questions I am going to post 4 graphs which that will get us part, if not all, the way there.
So, we compare certain metrics from the 12/13 season to the 13/14 season, using league data only (incentives).
These charts show Arsenal’s rolling share of the shots taken throughout their fixture lists. Arsenal were recording a higher percentage share of the shots in 12/13 than they currently are in 13/14. This is not a good thing.
Some folk may point to shot quality/locations but there’s usually a reason that teams take less shots and/or concede more shots and, usually, those reasons aren’t positive.
Shots On Target Ratio
A bit noisier, but a few things stand out: This time last year once the horrendous injury list had eased Arsenal went on a season saving run of form to finish 4th ahead of the Tottenham. A part of that form was due to an improvement down the strecth in Arsenal’s SoTR which picks up from game 23 or so and finished a fraction shy of 60%.
This season (13/14) Arsenal’s SoTR was pretty good, if not elite, for the first 22 or so games before nosediving. Injury lists play their part, as do quality of opposition issues. Still, it appears that Arsenal won’t be able to equal last years ~59% SoTR number. Arsenal’s 13/14 number is currently at 55.3%.
Goal% = Goals for/Total Goals(goals for+goals against)
Goal% is driven by a teams shots and target ratio and its PDO number. Arsenal’s 12/13 number consistently improved from around the 10 or 11 game mark – driven by SoTR (above) and an improving PDO.
Arsenal’s 13/14 Goal% was driven by good, not great, SoTR and a super high PDO that was at 110 or higher for 21 of the 31 weeks of the season so far. League average PDO is 100. Teams who spend a high amount of minutes in leading positions will post PDO’s north of 100.
We can see that Arsenal’s 13/14 Goal% has cooled off and this is due to SoTR cooling off by a few percentage points and a gradual cooling of PDO.
Arsenal’s shots and shots on target numbers may not have convinced everyone that there is real year on year decline and that’s ok. Maybe goal% didn’t convince anyone either! How about we look at points% then?
Points% = points/total points available
This graph is super cool in a scary kinda way. We can see that Arsenal showed amazing improvement in the second half of 12/13 (SoTR, PDO improved). Arsenal’s 13/14 season looks like it is going the other way. Decline, decay, injury-hit squad unable to cope with a tough sked, tactics or whatever. It is a frightening graph.
Whichever we slice the information it doesn’t look good:
In short: Context is important, inuries to key talent, lack of striker and wing options may have handicapped Arsenal’s ability to post better underlying numbers. The question is by how much have those issues handicapped Arsenal? We don’t know.
Arsenal may well surpass last seasons points total but they may well do so having posted poorer shots and shots on target numbers. People may point to shots quality (and some score effects) and say “who cares if they are shooting less but shooting better” and you know what, maybe they’re right, but for me I would rather a team posts high percentages of the shots and shots on target share whilst still trying to take the very best quality of shot that they can.