NEW YORK -- An early rally faded on the stock market Friday, leaving indexes down about 3 percent for the week as worries resurfaced about a breakup of the euro.

BlackBerry maker Research in Motion plunged after slashing its forecast for holiday sales.

The Dow Jones industrial average edged down about 2 points, but it had been up as many as 99 points after the Italian government won a confidence vote on austerity measures. It turned mixed around midday as Fitch warned that it might downgrade the debt of Italy, Spain and four other countries that use the euro.

Materials and industrial companies rose, signaling that traders expect the economic recovery to remain on track. Utilities, health care and consumer staples companies lagged the market as traders sold stocks that are considered to be safer when the economy is weak.

Delta to expand flights at New York's LaGuardia

NEW YORK -- Delta Air Lines plans a massive flight expansion out of New York's LaGuardia airport, hoping to improve its competitive edge against its two biggest rivals in one of the nation's most important air travel markets.

Delta said Friday that the additions make it the biggest airline between the New York area and other cities in the U.S., as it adds routes that target American Airlines and put it in a better position to compete against United Continental.

That should help it grab more high-paying business travelers, a critical passenger segment in major cities like New York.

The list of added cities reads like a map of the hubs of competing airlines. Delta is adding Miami and Dallas, both American Airlines hubs. It will also fly to Houston and Denver, which are United hubs, and Charlotte, -- a hub for US Airways. In all, it will add more than 100 flights to 29 new destinations.

Charleston, where Delta is the biggest carrier, was not among the cities identified in Friday's expansion.

Holiday sales upgraded by 2 market researchers

NEW YORK -- ShopperTrak, a Chicago-based research firm, said Friday it is upgrading its holiday sales forecast, a day after the nation's largest retail group boosted its outlook.

ShopperTrak now believes that sales for the November and December period combined will rise 3.7 percent. That's up from the original 3 percent growth forecast issued in September when the economy's recovery looked more uncertain.

The 3.7 percent forecast is still below the 4.1 percent growth registered in the year-ago period, according to ShopperTrak's measure.

The National Retail Federation said Thursday it now expects holiday sales to rise 3.8 percent, up from its 2.8 percent forecast in early October.

ShopperTrak measures foot traffic in 25,000 stores in the U.S. and blends those figures with economic data.

Equipment rental firms announce $1.9 billion deal

NEW YORK -- United Rentals Inc. said Friday it has agreed to buy rival equipment rental company RSC Holdings Inc. for about $1.9 billion in cash and stock.

United Rentals said the deal is expected to accelerate its growth with industrial customers, lower costs and provide a less volatile revenue stream. United said it has identified $200 million in potential cost savings.

United is the world's largest equipment rental company, with a network of 541 rental locations. RSC Holdings has a network of 452 branches.