Those wild spikes don't give me a lot of confidence in the data
The biggest spikes look like the correspond to new year. So my guess is that the spikes are vacations and show the difference between home PC and office PC usage.
You can see the same spikes on e.g. Googles IPv6 chart - when people are away from work IPv6 penetration goes up, when people are at work it goes down.
Those wild spikes don't give me a lot of confidence in the data
The biggest spikes look like the correspond to new year. So my guess is that the spikes are vacations and show the difference between home PC and office PC usage.
You can see the same spikes on e.g. Googles IPv6 chart - when people are away from work IPv6 penetration goes up, when people are at work it goes down.