When the capital falls below certain minimums rating agencies cut ratings, making it harder to sell coverage.
Reruns of "The Big Bang Theory" helped bolster TBS's ratings, making the channel the No. 1-rated cable channel among adults ages 18 to 49.
Errors in rating mortgage securities undermined the agencies' credibility with other types of ratings, making the credit crunch worse, argues Herring, who is also co-director of the Wharton Financial Institutions Center.
With MBIA's backing, First Alliance's mortgage-backed notes were awarded Wall Street's highest credit ratings, making them more attractive to institutional investors.
Analysts and investors are worried that State Street's continued losses on bond funds and other investments could cause credit agencies to lower their ratings, making it more costly for it to finance continuing operations.
The final was watched by an average of 11.7 million viewers, a million more than last year and reversing a two-year decline in ratings, making it the biggest show of 2015 so far.
