For investors

Press releases:
Fitch
Moody's
- 2010: 08 Feb 2010, 27 Apr 2010
- 2009: 21 Jan 2009, 06 Feb 2009, 27 Apr 2009, 13 May 2009, 15 Jun 2009, 07 Jul 2009
- 2006: 20 Apr 2006, 08 May 2006 (1), 08 May 2006 (2), 24 May 2006, 12 Jun 2006
S&P
- 2011: 31 Jan 2011
- 2010: 19 Mar 2010, 24 Sep 2010 (1), 24 Sep 2010 (2), 24 Dec 2010
- 2009: 16 Jun 2009 (1), 16 Jun 2009 (2), 16 Jul 2009, 16 Sep 2009 (1), 16 Sep 2009 (2)
- 2008: 04 Apr 2008, 18 Apr 2008 (1), 18 Apr 2008 (2), 29 Apr 2008 (1), 29 Apr 2008 (2), 25 Nov 2008