Corporate governance ratings
National corporate governance rating assigned by the Russian Institute of Directors.
| Date of assignment | Corporate governance rating |
| July 25, 2007 | 7+ |
| December 29, 2009 | 8 |
| December 6, 2013 | 7+ |
| November 14, 2016 | 7++ |
| March 29, 2018 | 7++ |