U.S. vehicle-sales events tied to the holidays go into full swing each year between Christmas and New Year’s Day, one of the industry’s strongest periods for car buying.

But a trend indicates auto makers and dealers are keeping busy with such sales throughout the year, says Jon Swallen, Kantar Media’s senior vice president-research.

Until recently, “sale-a-thons” and the like typically were held around certain holidays, such as President’s Day and the Fourth of July.

“But they’ve become a year-round phenomenon,” Swallen says. “We have not seen a single week without an auto company or dealer somewhere holding a sale or advertising one.”

Hyped sales programs featuring particular brands of cars accounted for 33% of advertising by regional and metro dealer groups, he says at a recent J.D. Power and Associates conference.

National television spots continue to account for 50% of auto makers’ advertising. However, many TV ads now urge consumers to go to another medium: the Internet, especially auto maker and dealer social-media sites.

“We’re seeing more campaigns in which TV, print and website ads are directing consumers to Facebook sites,” Swallen says. “Tactics for online and offline integration continues to evolve.”