Netflix is widely acknowledged to make up a large chunk of downstream internet traffic, and the company is now using that position to start charting how fast ISPs can stream movies to customers. Every month, it's announced, it will post the average download speeds for US video streaming. Netflix has published broad speed measurements before, but now it's creating an ongoing tally of how ISPs are doing, complete with indications of whether a service provider has moved up or down. It's also started differentiating by service, separating things like Verizon's FiOS and DSL offerings.

The results, right now, are pretty much what you'd expect: Google Fiber leads by a solid margin at an average of 2.55Mbps, with Verizon FiOS in second place, and mobile networks round out the very bottom of the list. AT&T was called out for poor performance on both U-verse home broadband and mobile networks. As people have pointed out before, Netflix's numbers aren't necessarily great indicators of either how fast networks can run or which ISP is best overall. The company also points out in its blog post that factors like home routers or encoding differences mean that "the average performance is well below the peak performance."

What this does do, however, is provide a reasonable estimate of how well its streaming video runs overall in real-world conditions. Likewise, it gives Netflix a platform to point out sudden service drops — like the kind that would happen if an ISP began throttling. The full list of ISPs and services can be seen below.

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