20110602 wall street 54
Traders work on the floor of the New York Stock Exchange as concerns about the health of the American economy continue grow. - 

Kai Ryssdal talks with Marketplace New York bureau chief Heidi Moore and CNBC's John Carney about the breaking news of the afternoon: Standard & Poor's decision to officially downgrade U.S. long-term debt from AAA status to AA+.

Here's how Moore explained it:

Heidi Moore: They downgraded the U.S. credit rating. It's like cutting our credit score. We went from a AAA to a AA+ -- which is more than people expected; people thought we'd just be a AA. The importance of this is largely psychological -- we've always been a AAA country. But now that we are a AA+, that's what everyone else will be too. I think everyone else will follow us.

Carney agreed that other countries would be downgraded as well:

John Carney: Remember, we're the country that supports people when they get in trouble. If our credit rating is lower, so is everybody else's.

To stay optimistic:

Moore: The same way they say 'Age ain't nothing but a number,' a credit rating ain't nothing but a letter.

For more analysis, click "Listen to this story" at the top of the page.