The Dow Jones industrial average fell 33 points to 13,544 shortly after 10 a.m. The Labor Department reported early Thursday that 382,000 people applied for unemployment benefits last week. When applications consistently top 375,000, it suggests hiring is too weak to lower the unemployment rate.
CarMax sank 6 percent after the chain of used-car dealers reported essentially flat quarterly net income, below analysts' expectations. Costs surged as CarMax opened more dealerships. Its stock lost $1.90 to $30.07.
ConAgra Foods Inc. jumped 7 percent. The maker of Healthy Choice packaged meals and Slim Jim beef jerky said its profit more than doubled, helped by lower food costs and a strong gain from a hedge on commodity prices. ConAgra's stock rose $1.50 to $27.15.
The real-estate website Trulia soared 32 percent in its first day of trading. Trulia priced its initial public offering at $17 on Wednesday, raising $102 million. Trulia's stock was already up to $22.70 less than an hour after the opening bell.
Weak economic figures weighed on markets in Europe and Asia. A gauge of European Union business activity slipped to its lowest level in more than three years.
Back in the U.S., the broader Standard & Poor's 500 index fell eight points to 1,453, and the Nasdaq composite index dropped 20 points to 3,162.
The three major indexes remain up more than 3 percent in September, historically the worst month for stocks. Since 1950, the S&P 500 has averaged a drop of 0.5 percent for the month. The Dow has lost an average of 0.8 percent.