Radnor-based Lincoln's 35 percent slide was the biggest of life insurers in the Standard & Poor's 500 stock index, a group that has come under pressure to raise money ahead of anticipated credit losses.

Lincoln's shares closed at $18.31, down $9.66 or 34.54 percent, on the New York Stock Exchange. That whacked $2.48 billion from Lincoln's value. The shares are off 57 percent this month.

"These are unprecedented times in the financial markets, and investor concern is punishing all of the financial-sector stocks," said Laurel O'Brien, a spokeswoman for Lincoln, which has its marketing name Lincoln Financial on the Eagles stadium in South Philadelphia.

"There is no specific news about LNC that would account for this level of pressure on the stock," O'Brien said.

To Morris Segall, president of SPG Trend Advisors, an economic-research firm in Baltimore, the share plunge was an ominous sign that "the life insurance companies, which I thought were going to be the last man standing, are getting nailed."

The only major life insurer to gain value yesterday was MetLife Inc., which raised $2 billion in a stock sale after saying this week that its third-quarter earnings would be lower than expected largely because of troubles in the financial markets.

Shares in MetLife, the largest U.S. life insurer, climbed $1, or 3.7 percent, to close at $28 on the New York Stock Exchange.

The Hartford Financial Services Group Inc. said Monday that it would receive a $2.5 billion capital investment from Allianz SE, a German financial giant. The deal came as Hartford announced a capital loss of $2.1 billion to $2.2 billion in the third quarter because of bad investments.

Despite the planned infusion of cash, Hartford's shares fell 19.11 percent yesterday, or $4.75, to close at $20.11 on the New York Stock Exchange.

Other major life insurers to fall yesterday included: Prudential Financial Inc., down $10.02, or 23.15 percent, to $33.27; Principal Financial Group Inc., off $5.95, or 27.37 percent, at $15.79; and Unum Group, down $6.22, or 29.63 percent, at $14.77.

Thomas V. Cholnoky, who covers life insurers for the Goldman Sachs Group Inc., said in a report that the notion was changing that life insurers offered a haven in troubled times.

"While many life insurance companies are in relatively stronger capital positions than their other financial-services brethren, the earnings and balance sheet pressures the industry now faces will continue to call into question whether this is a segment of the market in which to hide or one from which to run," Cholnoky said.