A Bad Week

Wall Street extended its steep decline Friday, propelling the Dow Jones industrials down more than 500 points over two days after investors gave in to mounting concerns that borrowing costs would climb for both companies and homeowners. It was the worst week for the Dow and the Standard & Poor's 500 index in five years.

Investors cast aside a stronger-than-expected read on the economy and maintained negative sentiment that dominated Thursday when the market shuddered amid worries over the U.S. mortgage and corporate lending markets. Investors globally took flight from equities, shifting cash into safer investments in Treasury bonds.