From Yahoo News:

NEW YORK - A disappointing sales forecast from Wal-Mart Stores Inc. sent stocks mostly lower Monday as investors worried that oil prices, which stabilized after last week's highs, would curb consumer spending and hurt companies' third-quarter earnings. Tech stocks eked out minimal gains.

...and...

Wal-Mart's warning about lower than expected August sales squelched the market's enthusiasm over falling oil prices. With its reach among consumers, Wal-Mart is seen as a barometer of an already struggling retail sector, and even the economy as a whole.

...and...

Wal-Mart lowered its August sales forecasts, citing lower back-to-school sales and lost business in Florida from Hurricane Charley. Sales at stores open at least a year — a standard for assessing a retailer's strength — are now expected to range from flat to 2 percent higher. Wal-Mart fell 85 cents to $53.80.

(Editor...gotcha ask what percentage is Florida sales in world wide picture? And what did you think Tom he was going to say the economy is in the tank? )