Already a mainstay inside the home, digital displays are accounting for an increasing share of out-of-home advertising as well. eMarketer predicts digital will take 53 percent of out-of-home advertising in the U.S. by 2018, a share worth $4.08 billion.

Digital’s share of out-of-home stands at 40.8 percent in 2015, up from 38.1 percent in 2014. Digital out-of-home (DOOH)—advertising delivered via internet-connected digital screens outside of the home—is expected to be one of the fastest growing paid media channels in regards to spending, following total digital and mobile.

“Digital screens outside the home that carry paid media are proliferating, from large digital billboards along highways to interactive touchscreens in restaurants, bars, malls, airports, taxi cabs and many other locations,” said eMarketer analyst Bryan Yeager. “Advertisers will direct spending into DOOH media as more inventory comes online, buying becomes more flexible, automated targeting and measurement capabilities improve, and OOH media firms increasingly push advertisers toward their digital offerings.”

eMarketer expects DOOH to demonstrate double-digit growth for a number of years. However, despite digital’s rise, total out-of-home advertising should shrink slightly. In 2015, it will account for 3.9 percent of total U.S. ad spending, and it is forecast to drop by 0.1 points each year through 2018.

Yeager adds, “Digital growth won’t be enough to increase OOH media’s share of total paid media spending in the U.S., because eMarketer assumes that funding for DOOH will primarily come from existing traditional OOH budgets that won’t be replaced. Remaining OOH dollars will be gradually moved to a mix of other digital channels.”