Wall Street set for lower open after Moody's rating cut; yields rise

Wall St set for lower open after Moody's rating cut; yields rise Wall Street's main indexes were on track to open lower on Monday as Treasury yields rose after Moody's downgraded the U.S. sovereign rating, sharpening focus on its mounting debt. Moody's cut the United States' sovereign credit rating to "Aa1" from "Aaa" late on Friday owing to concerns about its ballooning $36-trillion debt, becoming the last of the three major credit rating agencies to downgrade the country. It had first given the U.S. its pristine "Aaa" rating in 1919. "Nothing new, but it's putting a lot of things that…