Man I figure if you afk for more than 2 games straight, you are intentionally tanking your rank.
Also, what kind of pie chart is this? 42% is like over 86%. According to the text, only 9% are in "consistent AFK behaviour" but the tier 3+ percentage is 24%
Update: these are the correct values provided by RiotAether. In case you want to see the wrong numbers, here is what it was before.
Oh boy I never get to talk about Marketing Asset Production, here we go
While we were writing the blog, /u/barackprobama sent over a graph that is not this graph. I mentioned to him that we could include it, but I needed it in an editable file format so it could be localized. Our loc teams don't have licenses for the tool he uses, so he had to go recreate it in a different program. Since this was all happening shortly before I needed to send everything off, rather than start from scratch he pulled the editable file from a previous graph. This graph. Which by some strange coincidence uses the exact same numbers as the graph we posted today.
...so yeah we're fixing it (temp link here) and in the meantime the correct numbers are:
Tier 0: 42 > 82
Tier 1: 33 > 5.5
Tier 2: math
Tier 3+: 24 > 9