One of the few silver linings in what could become an increasingly depressed advertising market - those animated digital displays you see on the Underground. Screen Digest reckons their share of out-of-home advertising expenditure could grow from the current 3.1 percent to 10 percent in 2012 in western Europe - that’s from £158 million to £626 million. It’s not hard to see why advertisers like the displays - nevermind targetability and behavioural tracking - digital displays make for animated billboards. “This growth will happen despite the sluggish advertising market in traditional media, including TV and the press,” researchers said. It’s a market driven by plummeting costs of flat-panel displays, something the industry says makes for more return on investment - those on Underground escalators run by CBS (NYSE: CBS) Outdoor can make three to 10 times more revenue than static ads. Still, the UK leads the way, with 34 percent of digital out-of-home ad sales.