Citroën sales dropped slightly in 2015, 3.1% to be precise. The main brand was down 4.2%, the DS range -13.6% while the LCV models were up 6.6%. Whether sales go up or down isn't so much the issue but rather how profitable the brand is. I believe PSA (Peugeot and Citroën combined) are profitable.
Citroën: With the three best selling models down, an increase wasn't going to happen. The compact C4 came out in 2010 so is getting well along in its model cycle. The C3 was released in 2009 so even older. Hardly surprising the result in 2015. New models such as the C4 Cactus is going well though.
DS: In 2009, the DS range was introduced, the cars based on Citroën models, but more upmarket. For now it hasn't been that successful but is now being pushed more energetically by PSA. It's going to be a long road to establish, as winning sales in the premium segment is tough. PSA seem in this for the long haul and that is what is needed.
Citroën LCVs: All four models here had increases so it is the most successful area for the company in 2015. I thought of adding the models into the car section but didn't.
Data source: PSA.