The new Mustang, which made its debut in the fall of 2004, has been a bright spot for Ford at a time when bright spots have been few. So when Mustang sales fell by 19 percent in January and February compared with the same months in 2006, Ford executives became a little concerned.

"It's gotten our attention because when a high-volume product like that declines as much as that, we want to see what we might want to do," said George Pipas, Ford Motor Co.'s top sales analyst.

A drop in Mustang sales should be a concern for Ford: Overall U.S. sales slipped 8 percent last year. The company sold 160,975 Mustangs in 2005 and 166,530 in 2006, big numbers in the midsize sports coupe market.

"It did phenomenally well for a while, due in part to (it being) really the only car in the segment," said David Lucas, vice president of Autodata Corp.

It could be too soon, however, to write of the Mustang, Pipas said. "Two months is hardly a litmus test for the entire year, particularly when the two months aren't big sales months for anything, let alone two-door sports coupes," he said.
Ford is working to keep the Mustang fresh with new variations that keep the car exciting, said spokesman Alan Hall.

The company just began shipping new versions of a Shelby GT Mustang, and sometime next year, it plans a dark-green "Bullitt" version reminiscent of the 1968 Fastback Mustang GT that Steve McQueen drove in the classic movie.

Competition for the Mustang is only going to get worse when Dodge resurrects the Challenger muscle car in 2008 and Chevrolet comes out with the new Camaro early in 2009.