Also to be noted that eventough BMW and Audi sold more cars than Merc, the percentage of growth is higher for Merc compared to the other two
Yep, but that's due to two reasons mainly:
1. new or completely revamped high-volume models introduced
2. MB has finally resolved the issue with dealership network in China
So, it's natural MB growth has been higher compared to BMW & Audi. The growth generated by closing the gap in China due to dealership issue is to flatten, so the CLA, GLA & the revamped C-class & S-class sales will be sales growth generator for MB in 2014. .
Audi ... A3 sedan will generate the sales growth mostly in 2014. What else? Facelifed A6/A7, I guess. While the new A4, Q7 & TT are coming in very late 2014 or even in 2015? What will push Audi further is the next high volume model - and that is a city car based on VW Up! and a Q1 mini-SUV.
BMW ... I guess the new 2er series (especially the 2er Active Tourer) will push the sales growth for BMW in 2014. To some extent X4, 4er GC & i3 too. Revamped X5 & X6 will generate some growth too (although X5 sales have been already high) , facelifted 1er & X3 will contribute to sales growth too.
But mainly the growth now is to be generated by product portfolio expansion - especially with the new downsized high-volume models, and with numerous mid-sized & full-sized niche models.
Not to mention the race will also depend on how quickly the production capacities will be expanded - especially in China, USA & Latin America. Since all 3 experience high demand which is very much limited by limited production capacities (for certain models).