US STOCKS-Wall St falls for 3rd day as earnings disappoint
* Dow in the red for the year
* Caterpillar falls after lower quarterly profit
* Indexes down: Dow 0.7 pct, S&P 0.6 pct, Nasdaq 0.4 pct (Updates to late afternoon)
By Caroline Valetkevitch
July 23 (Reuters) - Wall Street fell for the third straight day on Thursday following disappointing results and forecasts from companies including 3M and Caterpillar, adding to U.S. profit concerns.
The manufacturing companies' declines helped push the Dow Jones industrial average back into the red for the year. Also hurting the Dow was American Express, down 2.6 percent at $76.95 after revenue missed expectations.
Caterpillar shares fell 3.7 percent to $76.88 and hit a four-year low of $76.65. The world's largest construction and mining equipment maker reported sales declines in key markets in a sluggish global economy.
"Companies such as Caterpillar are a litmus test for the global economy, especially at a time when the market is concerned about China's economy," said Mark Luschini, chief investment strategist at Janney Montgomery Scott in Philadelphia.
Nine of the 10 major S&P 500 sectors were lower with the utilities index leading the decliners with a 1.8 percent fall. Continuación...