Before the 1990s, Standard & Poor’s rated only a dozen sovereigns, almost all of them at the top
(AAA) rating category. Similarly, Moody’s had rated only 11 countries up to 1980, and they
were all in the investment grade range. This means that there is a fairly short experience in
observing the evolution of sovereign ratings, especially compared with the century-long
corporate ratings (Moody’s, 2003). Prior to the 1990s, the only “ratings” data available for
emerging economies are those assigned by publications such as Institutional Investor, and
Euromoney. In contrast to the credit rating agencies these are financial publications that have
rated sovereigns on the basis of surveys of investors and analysts. Although these ratings are
expressed on a scale that is broadly consistent with that of the credit rating agencies, it is
noteworthy that these are merely survey measures, while the rating agencies provide a
professional service to bond issuers and their ratings are a factor in investment mandates and
capital requirements.