The next time you’re sitting in traffic, consider this: In 2013, traffic jams in the U.S. cost consumers an estimated $124 billion. And that’s expected to increase by 50 percent by 2030, according to a report commissioned by the traffic data firm INRIX.

“That’s huge,” says Steve Banfield, chief marketing and product officer at  INRIX. “It’s crazy.”

The report found two-thirds of the cost of traffic jams is from wasted time and gas. Banfield says they even looked at time wasted planning for gridlock.

“In order to get where you need to be on time, you often factor in extra travel time before you even really need it,” he says.

All this can lead to health problems from stress. And researchers say the extra pollution caused by all those idling cars can lead to asthma attacks and strokes.

“Some of the pollutants that we looked at can travel tens or hundreds of miles away from the point of emission,” says Jonathan Levy, a professor of environmental health at Boston University’s School of Public Health.