CenturyLink (NYSE: CTL) has dropped to last place on Netflix's (NASDAQ: NFLX) March ISP speed index of streaming video performance. According to the streaming video provider, CenturyLink slid to number 15 on the March ISP Speed Index with an average of 1.53 Mbps.
Netflix noted that CenturyLink's average speed had dropped from 1.54 Mbps.
"CenturyLink, whose performance has steadily slid since last November, now ranks last in the index with an average monthly speed of 1.53 Mbps," Netflix said in a blog post. "By comparison, the slowest country we currently track -- Costa Rica -- posted average monthly performance of 1.87 Mbps in March."
Taking the top spot again amongst the largest broadband providers was Verizon FiOS (NYSE: VZ) with an average speed of 3.79 Mbps.
Despite Verizon's lead, the service provider's average streaming speed dropped slightly from its previous ranking in February.
Meanwhile, a number of Verizon's cable competitors including Bright House, Cox, Cablevision, Charter and Comcast (NASDAQ: CMCSA) also saw speeds drop during this period.
Out of the cable group, Cablevision, Comcast and Cox saw the largest drops in average bandwidth. Cox dropped to 3.63 Mbps, while Cablevision and Comcast dropped to 3.69 and 3.59 Mbps, respectively.
Overall, Netflix said that all of the monthly averages for ISPs on the list were affected by its complexity-based encoding that allowed it to boost streaming performance of TV shows and movies while using less bandwidth.
The video provider said that with about 80 percent of its catalog now having been re-encoded it is starting to impact the index.
"If you look at the US ISP Speed Index graph, you'll see the group of top performers started moving collectively down last month and again this month," Netflix said. "That movement as a group reflects more efficient streaming on those networks due to our encoding work."
- see this Netflix post
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