Cisco has released the latest version of its Mobile Visual Networking Index, now forecasting that video will account for 78% of all mobile data traffic by 2021, increasing in volume by 9x since 2016 when it accounted for 60% of mobile traffic.

The new target updates Cisco’s previous mobile video bullishness; in 2015 Cisco forecast that mobile video would account for 72% of all mobile traffic by 2019. Overall, Cisco is forecasting that 38 out of the 49 exabytes per month that will cross mobile networks in 2021 will be video.

Mobile video continues to experience a perfect storm of underlying enablers including an increase in the number of mobile-connected devices per capita (1.5 in 2021), increase in average mobile connection speeds (over 20 mbps in 2021), increase in smartphones (over 50% of all global devices in 2021) and increases in mobile network capacity and WiFi hotspots.

Cisco also highlighted other interesting trends, 2 of which affect video. First is that Cisco is seeing instances of “reverse migration” of mobile traffic from WiFi onto carrier networks, which it attributed to the availability of unlimited data plans, which are still relatively rare.

However, T-Mobile’s Binge On is, in effect, an unlimited plan for watching video from over 100 sources. Cisco doesn’t specifically call out T-Mobile, but it seems like there’s a connection. In addition, the zero-rating of video services (DirecTV Now & AT&T, Go90/etc. & Verizon) drives more mobile traffic onto the network and off WiFi.

Finally, Cisco is forecasting just 1.5% of mobile traffic will be 5G in 2021, a relatively low number that underscores how long it will take for 5G networks to fully roll out. This is interesting in the context of AT&T saying its Time Warner acquisition would accelerate 5G rollouts. That may be, but Cisco’s forecast suggests it will be a long time before the marriage of video and 5G will have a big impact.

The mobile VNI is available here.