Companies lose a lot more laptops than they disclose, according to a report published Monday.

According to a study of 106 major U.S. airports and 800 business travelers published by the Ponemon Institute and Dell Computer, about 12,000 laptops are lost in airports each week. Only 30 percent of travelers ever recover the lost devices. Nearly half of the travelers say their laptops contain customer data or confidential business information.

“It’s staggering to learn that up to 600,000 laptops are lost in U.S. airports annually, many containing sensitive information that companies must account for,” said Larry Ponemon, chairman and founder of the Ponemon Institute. “IT departments must re-evaluate the steps they’re taking to protect mobile professionals, the laptops they carry, and company data stored on mobile devices.”