The Dow Jones industrial average shed 35.79 points to close at 6,660.69, for its fourth straight losing session. The blue-chip barometer, which slid nearly 61 points after surrendering an opening 12-point gain, has lost about 223 points over the past four sessions, nearly halving the year's gains to 3.3 percent.
Decliners outnumbered advancers by nearly a 2-to-1 margin on the New York Stock Exchange, with 1,673 up, 859 down and 789 unchanged. NYSE volume totaled 445.54 million shares vs. 542.77 million yesterday.
The Standard & Poor's 500-stock list fell 5.52 to 765.00, and the NYSE's composite index fell 2.73 to 402.78. The Nasdaq composite index fell 11.02 to 1,352.81, and the American Stock Exchange composite index fell 2.00 to 586.16.
Broad-market measures were pressured by another weak day in the bond market, where the yield on the 30-year Treasury bond - a key determinant of corporate and consumer borrowing costs - rose from late Friday's 6.88 percent to 6.94 percent. The long-bond yield hasn't finished a day at that level since late September.
IBM was the Dow's biggest decliner, sliding for the fourth straight session in the aftermath of the computer maker's fourth-quarter results. But other leading computer-industry bellwethers held up better than most blue-chips against the profit-taking.