NEW YORK » Wall Street plunged for a second day, triggered by computer gear maker Cisco Systems warning of slumping demand and retailers reporting weak sales for October.

Concerns about widespread economic weakness sent the major stock indexes down more than 4 percent yesterday, including the Dow Jones industrial average, which tumbled more than 440 points.

Major indexes have lost about 10 percent since Barack Obama was elected president - a vote preceded by a steep rally - and the losses represent the Dow's worst two-day percentage decline since the October 1987 crash.

Paper losses during that time in U.S. stocks came to $1.2 trillion, according to the Dow Jones Wilshire 5000 composite index, which represents nearly all stocks traded in America.

Comments from Cisco that it saw a steep drop in orders in October and reports from retailers that consumers are skipping trips to the mall provided fresh evidence of the economy's struggles. Worries about automakers and the financial sector compounded investors' unease.

A day ahead of today's key October employment report, a widely watched barometer of the economy's health, the Labor Department said the number of people continuing to draw unemployment benefits jumped to a 25-year high.

The increase by 122,000 to 3.84 million in late October marked the highest level since late February 1983, when the economy was being buffeted by a protracted recession.

Yesterday's rout follows a drop of more than 5 percent in the market Wednesday that saw the Dow plunge nearly 500 points as investors fretted that weak readings on employment and downcast profit forecasts and job cuts from financial companies to steelmakers signaled broad economic troubles.

The Dow fell 443.48, or 4.85 percent, to 8,695.79 after falling as much as 502 in the final five minutes of trading. The blue chips remain 520 points, or 6.4 percent, above 8,176, their Oct. 27 closing low from the market's yearlong decline.

The Standard & Poor's 500 index fell 47.89, or 5.03 percent, to 904.88, and the Nasdaq composite index fell 72.94, or 4.34 percent, to 1,608.70.

Over the past two days, the Dow is down 9.7 percent, the S&P 500 index is off 10 percent and the Nasdaq is down 9.6 percent.

The Russell 2000 index of smaller companies fell 18.80, or 3.65 percent, to 495.84 yesterday, bringing its two-day decline to 9.2 percent.

Declining issues outnumbered advancers by about 5 to 1 on the New York Stock Exchange, where volume came to 1.53 billion shares.

The dollar traded mixed against most other major currencies, while gold prices fell.

Light, sweet crude fell $4.53 to settle at $60.77 a barrel on the New York Mercantile Exchange as fears of a slowing economy led to predictions demand will fall.