| - | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 |
| C3 | 81,00% | 80,00% | 82,00% | 82,00% | 80,00% | 80,00% | 78,90% | 79,60% | 81,19% | 81,20% | 80,44% | 80,28% | 81,05% |
| HHI | 26,03% | 25,82% | 26,82% | 27,42% | 27,14% | 26,22% | 25,60% | 25,67% | 26,20% | 25,90% | 25,64% | 24,44% | 24,72% |