They had enormous success under their previous coach, Pep Guardiola who left the team after last season. He was replaced by Tito Vilanova, Pep's assistant. Tito has continued the same philosophy, but this season under such high standards is a bit of a disappointment. The Barca team started so well in the beginning of the season but seemed to lose their way and with 4 trophies available, they will only win one.
So, I pulled together some data and I had a theory that I could visualize the data and demonstrate that Tito's absence during the middle of the season correlated (and presumedly caused) the dip in form to Barca. See, Tito took a leave of absence during the season for treatment for his cancer.
In the charts below, I took all the games Barca has played so far this season in La Liga, La Supercopa, La Copa del Rey, and the Champions League. For each win I gave them 3 points, 1 point for a tie, and 0 points for a loss. Only La Liga actually counts points this way throughout the season, but the goal here was to see how many points did the team accumulate throughout the season and where did the team drop points by not winning. My data set had score, location, opponent, and date.
Blue is the accumulated points and red are the accumulated dropped points. I added reference lines for when Tito was away from the team.
Problem: data doesn't match my theory of tito's absence
Then I created the graph below. The bar size is the net margin of victory or loss over the season. Barca plays each team at least two times in every competition. One home and one away. (at the time of writing this there are still 4 games remaining in La Liga)
The color is % of the points won based on points available. Reds are less than 50% of the available points, greys are 50% of available points, and blues are more than 50% of available points.
This chart describes perfectly what happened to Barca's season. Real Madrid and Bayern Munich. Barcelona played Real Madrid 6 times, won once, tied twice and lost thrice. Barcelona played Bayern Munich and lost twice.
The result with Bayern Munich is well known; two losses by a net margin of -7. This ends up a point collection of 0% and average net margin of -3.5.
Barcelona did not win the Champions League because they played Bayern Munich. They lost the Supercopa and the Copa del Rey because they faced Real Madrid. They won La Liga because they beat all other teams. Simple.