Up 205% apparently, though few are seen by real human beings:

Perhaps surprisingly, Timothy doesn’t blame bad guys using bots for this surge in video views, although they play a part. Rather, he sees a huge spike in autoplay video running below the fold where people can’t see it. “This is a huge priority, and nobody knows what to do about it,” Timothy said, who also noted that the number of video ad networks has jumped from 50 in 2010 to 150 today, further muddling the supply chain. “We want to shine a light on it.”

I don't blame the advertisers for getting worked up over this—they're paying for bogus ad impressions—but I think they're totally wrong in thinking that the answer lies in getting the ads into the visitor's line of sight. An auto-playing video ad is the quickest way to get me to leave a page and not come back, and I know I'm not alone. Fix the "below the fold" problem and watch your potential readers abandon your site completely.