Rating Agency Reports
- Moody's - August 2021
- S&P Global Ratings - October 2019
- Moody's - June 2019
- S&P Global Ratings - September 2018
- Moody's - December 2017
- Moody's - May 2016
- Fitch - August 2011
- Moody's - June 2011
- Fitch Recalibrated Ratings - May 2010
- Moody's - April 2010
- Fitch - September 2009
- Moody's - June 2005
- Moody's - October 2002
- Moody's - July 2002
- Moody's - May 2001
- Moody's - May 1997
- Moody's - January 1993
- Moody's - March 1992