"Over 100 companies globally have defaulted on their debt this year, affecting $302 billion worth of securities but that figure could rise as nearly 900 issuers are poised for credit downgrades, Standard & Poor's said on Monday. "The rise in defaults in 2008 is in sharp contrast with trends in prior years, when only 22 defaults were recorded in all of 2007 and 30 in 2006," said Diane Vazza, head of S&P's global fixed-income research group. The credit bubble appears to have been concentrated in the US. Of the 108 defaults this year, 86 are from the United States, 7 from Europe, 5 each from Asia and Canada, 3 from Latin America, and 2 from Russia. Furthermore, there are 897 issuers poised for downgrades, with the US topping the list of potential bond downgrades, Vazza said. The U.S. faces 531, or 59% entities at risk for downgrades, but that concentration partly reflects the larger rated population in the U.S. And Europe holds the next position, with 173, or 19% entities at risk for downgrades, she added. (Reporting by Jennifer Ablan, editing by Diane Craft)"