It's been a season of two halves for Arsenal and their beleaguered long-serving manager Arsene Wenger. For the 15 matches prior to defeat at Everton in mid-December - and even at the point they were 1-0 up in that game - Arsenal were flying high and dreaming of a first Premier League title since 2004.
In the 15 subsequent matches, however, their season has unravelled and it has all come apart at the seams. Arsenal are now sixth and clinging on to increasingly distant hopes of Champions League qualification and their darling Fourth Place Trophy.
But what exactly has happened to a group of players that so recently looked so capable of ending their title drought?
1 fewer goal scored per game
The most noticeable problem for Arsenal has been in front of goal, where there has been an been alarming decline. Arsenal scored 36 times in their first 15 games - hitting three or more against Liverpool, Watford, Hull, Chelsea. Swansea, Sunderland, Bournemouth and West Ham - but that has dropped to 25 in their most recent 15: a fall of 11 goals, or nearly one per game.
Alexis Sanchez, Theo Walcott and Mesut Ozil have all scored markedly less frequently, which may be down to the loss of Santi Cazorla's creativity due to injury, but any clubs would suffer when three of their princple attackers are blunted.
Arsenal have hit the target consistently, but have struggled to find the corners of late
4.6% drop in chances taken
Arsenal have been creating just as many chances since the Everton defeat as they were before that match. That is, they have had 76 shots on target in each period.
Clearly, their attacking play has remained imaginative and innovative, sufficiently at least to ensure they have plenty of goal-scoring opportunities.
However, the quantity of chances forged inside the six-yard box has dropped, while there has been less variety in terms of where goals are scored from. As shown by the above graphics, in Arsenal's first 15 games of the season, goals came from all over the pitch, with lots scored from outside or near the edge of the penalty area. That is no longer the case.
Arsenal scored nearly 16 per cent of their shots in their first 15 matches; that has fallen to 11.4 per cent since, a drop reflective of dwindling confidence levels in the team.
The bigger the circle, the better the chance. In their first 15 games, Arsenal had significantly more chances close to goal, giving them a much higher chance of scoring.
0.6 more goals leaked per game
There has been an even greater fall in defensive standards. While Laurent Koscielny's absence has been brutally exposed by Bayern Munich (twice) and more recently Crystal Palace, his presence has not been sufficient to halt the team's slide.
After shipping four goals to Liverpool on the opening weekend of the season when Rob Holding and Calum Chambers formed their centre-back partnership, Arsenal conceded just 11 goals in their next 14 games (totalling 15 in their first 15). In the 15 games since, however, 24 goals have been scored against them in the Premier League.
The number of chances they are conceding in open play has shot up, too, suggesting a lack of defensive discipline, which backs up Sam Allardyce's claims last week that Arsenal's full-backs "play like wingers, leaving Gabriel and Mustafi exposed". Teams have worked this out over the course of the season and used it to their own advantage.
37% increase in shots faced
Arsenal have allowed their opponents 74 shots on target in the second half of the season, which is more than nine of their Premier League rivals, including the likes of West Brom, West Ham and Southampton, while that figure is twice as many as Manchester City and United, with whom Arsenal presumably wish to be competing. 74 shots on target is a staggering 37 per cent increase on the 54 their opponents had in the first 15 games of their season.
There has also been a significant rise in shots faced from inside the penalty area, from 95 to 112, with the quality of chance they allow the opposition patently rising since the Everton defeat.
As the below graphics show, clear cut chances were hard to come by against Arsenal in the season's earlier stages. More recently, it has been far too easy for teams to find a way through.
The bigger the circle, the better the chance. In the first 15 games, Arsenal allowed their opponents far fewer high quality chances.
13.6% of shots faced go in
A number of factors have affected Arsenal's goalkeeping this season, not least the injury to first choice Petr Cech. That said, when Arsenal signed him it was hoped Cech could be the final piece in the puzzle.
Beyond the fact that he has patently been given too little protection, the former Chelsea keeper has also failed to produce the level of performance he did with such consistency for 10 years on the other side of London.
David Ospina and Emiliano Martinez have also proven incapable deputies, conceding eight goals in four Premier League appearances.
The number of opposition shots resulting in goals has crept up from 9.7 per cent in the first half of the season to 13.6 per cent in the second, while Cech and Ospina are responsible for the two errors leading to goals that Arsenal have committed in their last 15 games. Their keepers made no such mistakes in the first half of the campaign.
27% drop in win rate
The crux of it all has been a disappointing decline in results. Arsenal were second on 12th December, just three points behind Chelsea. In the league table for the period since, they are way down in mid-table (though it should be noted they have games in hand).
With seven losses and just six wins in their last 15 matches, their win rate has fallen from a title-challenging 67 per cent to an utterly abysmal 40 per cent. That rate extrapolated over the course of a 38-game season, that amounts to just 15 victories, or one more than ninth-placed Stoke managed last season.
Arsenal's troubles off the pitch surrounding the future of their manager have been an almighty distraction this season. On the pitch things have been nothing short of cataclysmic.