Airline shares fell Monday, helping drag down the broader market, as ash from a volcano in Iceland continued to disrupt air travel in Europe.
Most major European airports remained closed for a fifth day, and analysts estimated the shutdown has cost airlines at least $1 billion.
Ash can clog jet engines, prompting authorities to close airspace over much of Europe.
Among the largest U.S. carriers, only Southwest Airlines Co. stock rose Monday. JPMorgan upgraded Southwest, citing its revenue momentum and opportunity to benefit from consolidation in the industry, but the bank also upgraded shares of Delta Air Lines Inc., which fell.
The Amex airlines index fell 2 percent, with 11 of its 13 component stocks lower in afternoon trading.
The broad market also fell, as investors worried about airlines and banks. Regulators filed civil fraud charges Friday against Goldman Sachs just as Congress considers an overhaul of banking regulation laws. The measure could cover the types of risky securities at the center of the Goldman case.
In early afternoon trading, the Dow Jones industrial average fell 13 points to 11,005.
Oil prices dropped $1.76 to $81.48 a barrel on the New York Mercantile Exchange, partly out of fear that the disruption to air travel from the Icelandic volcano would cut demand for jet fuel and slow the global economic recovery.
JPMorgan upgraded Southwest to "Overweight" from "Underweight." Analyst Jamie Baker cited improvement in Southwest's revenue per available seat mile, a key measure of financial performance in the airline business.
The bank also upgraded Delta to "Overweight" from "Neutral" on improving fundamentals in the airline industry, while it cut Alaska to "Underweight" from "Neutral," suggesting that the shares were overvalued.
In afternoon trading, Southwest shares rose 34 cents, or 2.5 percent, to $13.72; Delta shares fell 37 cents, or 2.7 percent, to $13.50; and Alaska Air Group Inc. dropped $1.18, or 2.7 percent, to $41.91.
Shares of American Airlines parent AMR Corp. lost 40 cents, or 4.6 percent, to $8.39; United parent UAL Corp. dropped 98 cents, or 4.3 percent, to $21.85; Continental Airlines Inc. fell 88 cents, or 3.8 percent, to $22.10; and US Airways Group Inc. dipped 17 cents, or 2.4 percent, to $6.98.