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Lesson 11 min 20 XP

Credit Rating Agencies

How three private companies in New York determine borrowing costs for governments worldwide, and the controversy over their power.

The Big Three

Three companies -- Moody's, Standard & Poor's (S&P), and Fitch -- control roughly 95% of the global credit rating market. Their letter-grade ratings (AAA down to D) determine borrowing costs for governments, corporations, and financial products worldwide. A single downgrade can add hundreds of millions of dollars to a country's annual debt servicing costs. When S&P downgraded the United States from AAA in 2011, it sent shockwaves through global markets.

The agencies' power is partly regulatory. Many institutional investors -- pension funds, insurance companies, central banks -- are required by regulation to hold only investment-grade securities. When an agency downgrades a country or company below investment grade (from BBB- to BB+, the 'fallen angel' threshold), it triggers forced selling by these institutions, amplifying the market impact far beyond what the underlying risk change warrants.

Credit Rating Agencies | Model Diplomat