TECH STOCKS: Down Almost 2%TECH STOCKS: Down Almost 2%

Investor disappointment about Yahoo's second-quarter earnings, combined with bad news on the unemployment front, triggered a sell-off that sent all of our indexes plunging between 1% and 2% Thursday. Typifying the day, the Nasdaq-100 tracking stock (QQQ) closed at $31.61, down 59 cents, or 1.8%, on heavy volume of nearly 94 million shares.

Yahoo late Wednesday reported earnings that matched Wall Street's expectations. But investors, buoyed by the market's rapid rise in recent weeks, were apparently expecting more. Yelling the opposite of "Yahoo!" they sent the Internet portal company's stock down more than 8%, pulling other technology stocks down with it. Amazon.com and eBay shares dropped more than 5% and 2%, respectively. Hewlett-Packard was one of the day's biggest losers--for no obvious reason--with a 4.5% drop, while the value of Intel and Cisco Systems dropped 3%.

The Yahoo debacle indicates that investors expect tech companies to beat Wall Street estimates during the next several weeks. Adding to investor gloom was a report that the number of Americans filing unemployment claims last week rose to 439,000 from 430,000. Economists had predicted that number would drop to 420,000.

Our information 100 fell 4.76 points, or 1.8%, Thursday to close at 263.68, while the Nasdaq index fell 31.77, or 1.8%, to finish the day at 1,715.69. The Dow fell 120.17 points, or 1.3%, to close at 9,036.04, and the S&P 500 fell 13.54, or 1.4%, to finish the day at 988.67.