Facebook Says It’s Sorry It Vastly Overestimated Video Watch Time for Two Years
Facebook has issued a public apology in the wake of today’s report by the Wall Street Journal (WSJ) that, for two years, it overestimated average video watch time on the platform by between 60% and 80%, angering marketers who were buying ads to run against the clips and potentially steering their buys away from competitors such as YouTube, Twitter and TV networks, as well as misleading publishers about the performance of their content.
“About a month ago, we found an error in the way we calculate one of the video metrics on our dashboard — average duration of video viewed,” wrote David Fischer, vp of business and marketing partnerships for Facebook, in a blog post. “The metric should have reflected the total time spent watching a video divided by the total number of people who played the video. But it didn’t — it reflected the total time spent watching a video divided by only the number of ‘views’ of a video (that is, when the video was watched for three or more seconds). And so the miscalculation overstated this metric. While this is only one of the many metrics marketers look at, we take any mistake seriously.”
According to WSJ, Facebook only counted video views of more than three seconds when calculating its “Average Duration of Video Viewed” metric, inflating the average view durations it reported. Facebook has now introduced a new metric to replace it, “Average Watch Time,” that will count video views of any duration.
Facebook disclosed its errors several weeks ago in a post on its “Advertiser Help Center,” but the issue wasn’t widely known to the public until today.
“As soon as we discovered the discrepancy, we fixed it,” said Fischer in today’s blog post. “We informed our partners and made sure to put a notice in the product itself so that anyone who went into their dashboard could understand our error. We have also reviewed our other video metrics on the dashboard and have found that this has no impact on video numbers we have shared in the past, such as time spent watching video or the number of video views. We want our clients to know that this miscalculation has not and will not going forward have an impact on billing or how media mix models value their Facebook video investments.”
Ad buying giant Publicis Media, which purchased $77 billion in ads in 2015, didn’t buy Facebook’s excuses. In a memo to clients, published by WSJ, Publicis said, “In an effort to distance themselves from the incorrect metrics, Facebook is deprecating [the old metrics] and introducing ‘new’ metrics in September. Essentially, they’re coming up with new names for what they were meant to measure in the first place.”